EP1177386A1

EP1177386A1 - Sleeve bolt

Info

Publication number: EP1177386A1
Application number: EP00922358A
Authority: EP
Inventors: Pierre R. Mcduff; Lang Nguyen
Original assignee: Cobra Anchors Co Ltd
Current assignee: Cobra Anchors Co Ltd
Priority date: 1999-04-30
Filing date: 2000-05-01
Publication date: 2002-02-06
Also published as: CA2301352A1; WO2000070232A1; AU4278700A

Abstract

A sleeve bolt (B) for insertion in a hole (H) delimited by a wall comprises a threaded fastener (40) and an expansion member (41). The threaded fastener (40) has a stem (50) that includes a proximal cylindrical shank (52) and a distal threaded section (54). The shank (52) has substantially the diameter of the hole (H) and defines at a distal end thereof a conical expander portion (56). The expansion member (41) comprises a distal threaded member (44) and a proximal expansion wedge (42), the threaded member (44) being threadably engaged to the threaded section (54) of the stem (50). The expansion wedge (42) has a proximal end (68) adapted, upon axial displacement of the expansion member (41) towards the shank (52) resulting from a rotation of the stem (50), to engage the conical expander portion (56) such as to expand the proximal end (68) of the expansion wedge (42) outwardly into engagement with the wall. The expansion wedge (42) frictionally engages the wall upon introduction of the stem (50) in the hole, whereas the threaded member (44) is spaced from the wall. The threaded member (44) comprises a distal conical section (62) which tapers towards the expansion wedge (42) and which is adapted to displace towards and relative to both the expander portion (56) and the expansion wedge (42) such that the conical section (62) causes a distal end (70) of the expansion wedge (42) to expand outwardly into engagement with the wall.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to fasteners and, more particularly, to expandable fasteners for mounting to concrete structures, and the like.

2. Description of the Prior Art Expandable anchors of many different types are already known. More particularly, expandable anchors have been developed for insertion into a hole formed in a support structure such that an expansion sleeve of the anchor may be selectively expanded into frictional contact with the inside peripheral surface of the hole such that the anchor becomes frictionally anchored in the support structure. Typically, the expandable anchor includes an elongated expander member having* a threaded first end and a flared second end opposite the first end with a cylindrical surface extending between the first and second ends around which there is provided the aforementioned expansion sleeve which generally has the shape of a cylinder. The threaded first end is like a headless screw and extends outwardly of the support structure once the expandable anchor is positioned in the hole thereof. A nut threaded on the visible part of the threaded first end may be used as an actuating mechanism with an object to be secured to the support structure being typically located between the nut and the support structure as the threaded first end of the expandable anchor extends through this object. By rotating the nut, it engages the outer surface of the object and thus bears upon it such as to pull the expander member in an outward direction. As the expansion sleeve is already sufficiently frictionally engaged with the inside surface of the hole, when the expandable anchor is pulled by the rotation of the nut, the expansion sleeve stays substantially stationary in the hole and thus, as the expander member is pulled out of the hole, the flared second end of the expander member causes the radial expansion sleeve to expand outwardly thereby increasing a friction between the expansion sleeve and the hole and thus securing the expandable anchor therein.

Since the expansion sleeve must already be frictionally engaged with the hole before the expandable anchor is pulled, the outside diameter of the expansion sleeve must be similar to the inside diameter of the hole and even slightly greater therefrom in order to ensure an initial frictional contact therebetween which will then allow the expansion sleeve to remain still in the hole while the expander member is pulled outwardly thereof and thus allow the expansion sleeve to be expanded by the flared end of the expander member. This diameter of the expander member, at rest, results in that the expandable anchor when initially inserted in the hole must be driven with significant force therein as the expansion sleeve is already frictionally engaged with the inside wall of the hole. The flared end acts as a wedge to expand a distal end of the expansion sleeve into greater frictional contact with the inside of the hole.

Such conventional sleeve anchors are comprised of multiple components which consist of an anchor body, extension sleeves/spacers, expansion sleeve, post nut or head and flat washer. One of the drawbacks to the conventional type sleeve anchor is the high deflection that occurs when a tension load is applied to the anchor bolt. Another characteristic is the shear value is lower because the anchor bolt thread size is smaller than that the bolt diameter in the area the shear load is applied. Another issue is the anchor coming loose when used in vibratory loads . This is a result of the anchor components relaxing and coming loose over time.

Also known are undercut wedge anchors, wherein the hole formed in the support structure is enlarged at a distance from the visible opening of the hole such that the expansion sleeve may be subsequently inserted behind a shoulder defined at the junction of the enlarged area and the remainder of the hole. Once expanded, the expansion sleeve may abut this shoulder and thus retain the anchor in position in the support structure. A drawback of such undercut wedge anchor thus resides in that, after the hole has been defined in the support structure, a tool must be used to form the undercut before the anchor can actually be installed in the hole, whereby the forming of the undercut constitutes an additional step.

SUMMARY OF THE INVENTION

It is therefore an aim of the present invention to provide an improved expandable anchor for use in holes in various materials, e.g. concrete.

It is also an aim of the present invention to provide an expandable bolt, such as a sleeve bolt, having an expander member and an expansion member capable of spring-like deformation.

It is a still further aim of the present invention to provide an expandable bolt in which most of a shank diameter of the bolt is substantially equal to that of the hole which receives it .

It is a still further aim of the present invention to provide an expandable bolt having an expansion member provided only around a distal end of the bolt's shank. It is a still further aim of the present invention to provide an expandable bolt having an expansion wedge adapted to expand at a proximal end thereof and directly onto the bolt's shank.

It is a still further aim of the present invention to provide an expandable bolt having an expansion wedge adapted to expand also at a distal end thereof onto a threaded expander member mounted on the bolt's threaded distal end section.

It is a still further aim of the present invention to provide an expandable bolt having an expansion wedge adapted to provide friction with a wall of the receiving structure.

Therefore, in accordance with the present invention there is provided a sleeve bolt for insertion in a hole delimited by a wall, comprising a threaded fastener and an expansion means, said threaded fastener having a stem, said stem including a proximal stem section and a distal threaded section, said proximal stem section having substantially a diameter of the hole and being provided at a distal end thereof with an expander means, said expansion means being adapted to be threadably engaged onto said distal threaded section and having a proximal end adapted, upon axial displacement of said expansion means towards said proximal stem section resulting from a rotation of said stem, to engage said expander means such to expand outwardly into engagement with the wall.

Also in accordance with the present invention, there is provided a sleeve bolt for insertion in a hole delimited by a wall, comprising a threaded fastener and an expansion means, said threaded fastener having a stem, said stem including a proximal stem section and a distal threaded section, said proximal stem section being provided at a distal end thereof with an expander means, said expansion means being adapted to be threadably engaged onto said distal threaded section and having a proximal end adapted, upon axial displacement of said expansion means towards said proximal stem section resulting from a rotation of said stem, to engage said expander means such to expand outwardly into engagement with the wall .

Still in accordance with the present invention, there is provided a method of setting a sleeve bolt in a hole delimited by a wall, comprising the steps of: (a) providing a threaded fastener and an expansion means threadably engaged to a distal end of said fastener; (b) inserting said expansion means and part of said threaded fastener in the hole; (c) rotating sufficiently said fastener with said expansion means being frictionally engaged to the wall for causing said expansion means to displace towards a proximal end of said fastener and for causing a proximal end of said expansion means to be expanded by said fastener into engagement with the wall .

BRIEF DESCRIPTION OF THE DRAWINGS

Having thus generally described the nature of the invention, reference will now be made to the accompanying drawings, showing by way of illustration a preferred embodiment thereof, and in which:

Figs. 1 to 3 are front elevational views of a sleeve bolt in accordance with the present invention shown respectively in first, second and third positions thereof;

Figs. 4 to 6 are bottom plan views of the expansion sleeve of the sleeve bolt of Figs. 1 to 3;

Fig. 7 is a top plan view of the sleeve bolt of Figs. 1 to 3; Figs. 8 and 9 are respectively front elevational and top plan views of the fastener of the sleeve bolt of Figs. 1 to 3;

Figs. 10 and 11 are respectively front elevational and bottom plan views of the threaded member of the expansion sleeve of the sleeve bolt of Figs . 1 to 3 ;

Fig. 12 is a plan view of the expansion member of the expansion sleeve of the sleeve bolt of Figs. 1 to 3 , this expansion member being shown in its initial manufactured state, i.e. before being shaped for use in the sleeve bolt;

Figs. 13 to 15 are respectively front elevational and top and bottom plan views of the expansion member of Fig. 12, but shown in its position for mounting to the threaded member of Figs. 10 and 11;

Figs. 16 to 18 are respectively front elevational, vertical cross-sectional and top plan views of a second embodiment of the sleeve bolt of Figs. 1 to 3 , also in accordance with the present invention;

Figs. 19 to 21 are front elevational, vertical cross-sectional and top plan views of the home expansion sleeve of the sleeve bolt of Figs. 16 to 18;

Figs. 22 and 23 are front and left side elevational views, partly in cross-section, of a third embodiment of a sleeve bolt in accordance with the present invention;

Fig. 24 is a top plan view of the sleeve bolt of Fig. 23;

Figs. 25 and 26 are respectively side and cross-sectional front elevational views of a threaded member of an expansion member of the sleeve bolt of Figs. 22 and 23; Figs. 27 to 30 are respectively right side elevational, cross-sectional front elevational, top plan and inverted left side elevational views of an expansion wedge of the expansion member of the sleeve bolt of Figs. 22 and 23;

Fig. 31 is a front elevational of the expansion wedge of the third embodiment in an unfolded position thereof, i.e. as stamped or otherwise manufactured and before being formed for use in its form shown in Figs. 27 to 30;

Figs. 32 and 33 are front and left side elevational views, partly in cross-section, of a fourth embodiment of a sleeve bolt in accordance with the present invention;

Fig. 34 is a top plan view of the sleeve bolt of Fig. 23;

Figs. 35 and 36 are respectively side and cross-sectional front elevational views of a threaded member of an expansion member of the sleeve bolt of Figs. 32 and 33;

Figs. 37 to 40 are respectively right side elevational, cross-sectional front elevational, top plan and inverted left side elevational views of an expansion wedge of the expansion member of the sleeve bolt of Figs. 32 and 33;

Fig. 41 is a front elevational of the expansion wedge of the fourth embodiment in an unfolded position thereof, i.e. as stamped or otherwise manufactured and before being formed for use in its form shown in Figs. 37 to 40;

Figs. 42, 43 and 44 are cross-sectional elevational views of the sleeve bolt of Figs. 22 and 23 shown in three successive installation positions in a hole defined in a concrete structure; and

Figs. 42A, 43A and 44A are enlarged partial schematic cross-sectional elevational views of the sleeve bolt and concrete structure of Figs. 42, 43 and 44.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In accordance with the present invention, Figs. 1 to 3 illustrate a sleeve bolt A comprising a threaded fastener 10 and an expansion sleeve 12. The fastener 10 includes a stem 14 having a proximal smooth cylindrical section 16, a reduced diameter threaded distal section 18 and an intermediate frusto-conical section 20. The fastener 10 also includes a bolt head 22 and a washer 24, both to be located outside of the hole defined in a structure, in which hole the stem 14 is to be inserted such that an object may be held secure by the bolt head 22 against the structure.

The expansion sleeve 12 includes a cylindrical internally threaded member 26 (Figs. 10 and 11) and an expansion member 28 (Figs. 12 to 15) . The expansion member includes a central ring 30 and, for instance, three anchor legs 32 extending therefrom. When the threaded member 26 and the expansion member 28 are assembled together as in Figs. 1 to 6, narrow sections 34 of the legs 32 are lodged in notches 36 defined on the periphery of the threaded member 26.

The threaded section 18 of the fastener 10 is adapted to threadably mate with the threaded member 26 of the expansion sleeve 12 with the threaded section 18 extending through the central ring 30 and with the legs 32 extending exteriorly along the threaded section 18, as seen in a first or inoperative position of the sleeve bolt A shown in Fig. 1.

When the sleeve bolt A of Fig. 1 is positioned in the aforementioned hole defined in the support structure, the expansion sleeve 12 frictionally contacts the walls of the hole in a sufficient manner such that the subsequent rotation of the fastener 10 by way of its bolt head 22 will cause the fastener 10 to move further into the hole of the structure, as the expansion sleeve 12 remains stationary in the hole (in view of its frictional contact with the walls thereof) and in view of the threaded engagement of the distal section 18 of the fastener 10 with the threaded member 26 of the expansion sleeve 12. Indeed, the rotation of the fastener causes the same to displace through the expansion sleeve 12, whereby, as seen in Figs. 2 and 3, the expansion sleeve 12 is displaced relative to the fastener 10 such that the legs 32 thereof climb along the frusto-conical section 20 of the stem 14 of the fastener 10 and are forced outwardly by the frusto-conical section 20 until the proximal edges 38 of the legs 32 come into strong angled engagement with the walls of the hole. The angle of the legs 32 in Fig. 3 and their engagement with the walls of the hole prevent the bolt sleeve A from being forcibly removed form the hole.

In Figs. 16 to 21, a variant sleeve bolt A' includes the same fastener 10 which is now used with an expansion sleeve 12 ' having four legs 32 ' . The expansion sleeve 12 ' is also of unitary construction in that the threaded member and expansion members 26 and 28 of the sleeve bolt A of Figs. 1 to 15 are manufactured integrally with each other.

In Figs. 22 to 31, there is shown a further sleeve bolt B having a steel anchor body or threaded fastener 40 and an expansion member 41 which is comprised of an expansion wedge 42 and a threaded member 44 in the form of a nut . The threaded fastener 40 includes a proximal head 46 (e.g. hexagonal, although the head 46 could be flat, round, etc.), a large washer 48, and a stem 50 extending distally from the head 46 and adapted to be received in a hole defined in a support structure, such as concrete. The stem 50 includes a main cylindrical shank section 52 and a reduced diameter threaded section 54 defined at a distal end of the stem 50. The distal threaded section 54 is much shorter than the cylindrical shank section 52 extending between the head 46 and the distal threaded section 54. At a junction between the cylindrical shank and threaded sections 52 and 54, the cylindrical shank section 52 is provided with a frusto-conical or taper portion 56 which defines a flare. The head 46 is used for setting the sleeve bolt B as well as for providing the clamping/holding power needed to hold a fixture being attached in place to the support structure. Under the head 46, there are two locking nibs (not shown) that locate and keep the washer 48 in its axial position. As it will be seen in detail hereinafter, the taper portion 56 functions as part of the expansion mechanism that causes the expansion wedge 42 to expand at its proximal end when the bolt B is being installed.

The threaded member 44 is an internally threaded steel nut that is adapted to threadably engage the threaded section 54 of the stem 52 of the fastener 40 and that defines on its outside surface an external flare 62 which expands from a proximal end towards a distal end thereof. This external flare 62 interacts with the taper portion 56 of the threaded fastener 40 to expand the expansion wedge 42 as the bolt B is tightened, as it will be discussed in more detail hereinafter. The threaded member 44 at a proximal end thereof is provided with a series (e.g. a pair) of tabs 64 that extend outwardly (see Figs. 22 and 26) .

The expansion wedge 42 is made of spring steel and has a formed cone-shaped configuration. The expansion wedge 42 defines on opposite sides thereof rectangular and tapering slots 58 and 60, respectively (see Figs. 29 and 30) . The tabs 64 of the threaded member 44 interlock with the slots 58 and 60 of the expansion wedge 42 to link these two components together (see Figs. 22 and 23) so as to prevent them from spinning in the hole during installation and so as to drive the expansion wedge 42 onto the taper portion 56. This interlocking also aid in the alignment of thee components. This allows even expansion of the expansion wedge 42 during installation. The expansion wedge 42 is formed so that it provides constant interference with the concrete before and during installation, thus providing constant resistance to pullout or upward movement in the hole.

The washer 48 provides a means of minimizing friction between the head 46 and the fixture being attached to the support structure during installation. The increased diameter of the washer 48 increases the clamping surface area between the fixture being attached, thereby providing a more stable installation.

With reference to Figs. 42 to 44 and their enlarged versions in Figs. 42A to 44A, the sleeve bolt B is installed into a hole H drilled in a concrete support structure S by first hammering the bolt B along arrow 66 into the hole H (see Fig. 42), the bolt B extending through the fixture (not shown) destined to be held thereby against the support structure S, until the head 46 and the washer 48 are flush with the fixture surface. Some resistance is felt as a result of a pre-expanded upper portion 68 of the expansion wedge 42, which digs into the concrete wall of the support structure S and which is compressed while the bolt B is being hammered in the hole H. There is a slight clearance for the threaded member 44 with respect to the concrete wall such that there is no friction therebetween, thereby allowing for the threaded member 44 to move easily up the hole H.

As the installation torque is increased, the threaded member 44 begins to be drawn upward along the hole H with the expansion wedge 42 displacing therewith translationally (as being driven by the flare 62 of the threaded member 44 which is engaged against a distal end 70 of the expansion wedge 42) and rotatably (as being interlocked to the threaded member 44) . At one point, the expansion wedge 42 contact the taper portion 56 of the stem 50 such that further rotation of the fastener 40 forces the upper portion 68 of the expansion wedge 42 to climb along the taper portion 56 and thus to expand outwardly into the concrete wall, and create an undercut in the concrete wall. The further up the expansion wedge 42 is along the taper portion 56, the more it expands into the concrete thereby providing further interference between the expansion wedge 42, the fastener 40 and the concrete support structure S. In fact, the upper portion 68 of the expansion wedge 42 becomes imprisoned between the concrete wall and the taper portion 56. The shape of the upper portion 68 of the expansion wedge 42 ensures uniform expansion of thereof, thereby providing great resistance to upward movement and vibration.

The tabs 64 on the threaded member 44 are aligned with the slots 58 and 60 in the expansion wedge 42, thereby again providing a means of alignment and resistance to spinning during installation while also preventing the expansion wedge 42 from settling on the taper portion 56 prematurely, that is while the bolt B is translationally driven in the hole. In Figs. 43 and 43A, the tab 64 lodged in the tapering slot 60 forces the upper portion 68 of the expansion wedge 42 to expand outwardly further into contact with the concrete wall.

As the setting torque is increased, the stem 50 and the threaded member 44 are pulled and thus move upwardly with the flare 62 of the threaded member 44 (see Figs. 44 and 44A) , thereby forcing the distal end 70 of the expansion wedge 42 to expand outwardly into firm engagement with the concrete wall. Therefore, the distal end 70 of the expansion wedge 42 is forced outward by the flare 62 on the threaded member 44, forcing the distal end 70 of the expansion wedge 42 into the concrete wall and thus providing additional axial interference between the flare 62 on the threaded member 44 and the expansion wedge 42. The tabs 64 of the threaded member 44 prevent the upper portion 68 of the expansion wedge from collapsing inwardly. At this point, the sleeve bolt B is firmly set in the support structure S and the load can be applied. It is noted that this uniform expansion of the mechanism provides optimal resistance to upward movement and vibration.

Another function of this anchor B is the high resistance to shear loads, as a result of the bolt section 52 being at the maximum diameter at the point where the maximum shear force would be applied.

It is important to recognize that, in prior art sleeve bolts, the expansion sleeve extends, in one form or another, around the bolt's stem from the head of the bolt up to the conical expander member provided at the distal end of the stem, whereby the complete stem is of a reduced diameter, that is significantly smaller than the diameter of the hole which receives it as there need to be room between the concrete wall and the bolt's stem for the expansion sleeve, thereby reducing the strength of the sleeve bolt. In the present invention, the expansion sleeve, herein referred to as the expansion wedge 42, extends only at the reduced distal threaded end 54 of the bolt's stem 50 with the "full diameter"

(i.e. of almost the size of the hole H) constituting most of the bolt's stem 50, for a stronger sleeve bolt B.

In the present sleeve bolt B, it must also be noted that the initial friction with the concrete wall occurs at the expansion wedge 42 of the expansion member 40, as opposed to prior art sleeve bolts where initial friction is at the conical expander member provided at the distal end of the stem, and also that the conical expander member of the prior art is not connected to the expansion sleeve, whereby, upon rotation of the prior art fastener, the expansion sleeve remains stationary while the conical expander member gradually gets closer to the head of the fastener until it engages the expansion sleeve thereby causing the same to outwardly -expand at its lower distal end. In the present sleeve bolt B, both the expansion wedge 42

(i.e. the equivalent to the prior art's expansion sleeve) and the threaded member 44 (i.e. the equivalent to the prior art ' s conical expander member) displace along the stem 50 such that the expansion wedge 42 gets closer to the head 46 (as opposed to the prior art) thereby causing a proximal end 68 of the expansion wedge 42 to expand into the concrete wall. Furthermore, this gripping is conveniently effected very remotely from the proximal end of the hole H (i.e. from the head 46) thereby increasing the strength of the anchoring force of the bolt B in the support structure S. Figs. 32 to 41 illustrate a variant sleeve bolt B' of the sleeve bolt B of Figs. 22 to 31 in which the expansion wedge 42 ' is of different configuration, being exempt of the tapering slot 60 of bolt B, which acts on the expansion wedge 42 as seen in Figs. 43 and 43A, and having rather a T- shaped opening 58' and a straight slot 60'.

The present improved sleeve bolt B/B ' concept is thus designed to provide maximum tension and shear loading along with providing minimum anchor deflection as a result of the maximum expansion taking place at the bottom-most portion of the anchor bolt embedment.

Claims

CLAIMS :

1. A sleeve bolt for insertion in a hole delimited by a wall, comprising a threaded fastener and an expansion means, said threaded fastener having a stem, said stem including a proximal stem section and a distal threaded section, said proximal stem section having substantially a diameter of the hole and being provided at a distal end thereof with an expander means, said expansion means being adapted to be threadably engaged onto said distal threaded section and having a proximal end adapted, upon axial displacement of said expansion means towards said proximal stem section resulting from a rotation of said stem, to engage said expander means such to expand outwardly into engagement with the wall .

2. A sleeve bolt as defined in claim 1, wherein said expansion means comprise a distal threaded member and a proximal expansion wedge, said threaded member being adapted to be threadably engaged to said threaded section of said stem, said expansion wedge being adapted to frictionally engage the wall upon introduction of said stem in the hole while said threaded member is spaced from the wall such that, upon sufficient subsequent rotation of said stem, said expansion means displace towards said expander means .

3. A sleeve bolt as defined in claim 2, wherein a transversal size of said expander means reduces in direction of said distal threaded section of said stem such that, upon displacement of said expansion wedge along said distal threaded section and towards said expander means, a proximal end of said expansion wedge engages said expander means and gradually expands outwardly.

4. A sleeve bolt as defined in claim 3, wherein said expander means defines a taper.

5. A sleeve bolt as defined in claim 4, wherein said expander means comprises a frusto-conical portion.

6. A sleeve bolt as defined in claims 2 to 5, wherein said threaded member of said expansion means comprises a conical section which tapers towards said expansion wedge, said conical section being adapted, upon sufficient rotation of said stem and once said expansion wedge is substantially stationary onto said expander means, to displace towards and relative to both said expander means and said expansion wedge such that said conical section causes a distal end of said expansion wedge to expand outwardly into engagement with the wall .

7. A sleeve bolt as defined in claims 2 to 6, wherein said expansion wedge defines at least one opening means, said distal threaded member of said expansion means being engaged in said opening means such that said expansion wedge and said distal threaded member rotate jointly with respect to said stem.

8. A sleeve bolt as defined in claim 7, wherein said distal threaded member comprises a tab means extending into said opening means, said tab means being capable of displacing along said opening means, upon sufficient rotation of said stem and once said expansion wedge is substantially stationary onto said expander means, and of causing said expansion wedge to expand outwardly.

9. A sleeve bolt as defined in claim 8, wherein said expansion wedge defines a longitudinal slit extending along a whole length thereof and through said opening means, said opening means comprising a proximal end portion tapering in direction of expander means, whereby said tab means, upon engaging said proximal end portion of said opening means, cause said expansion wedge to gradually outwardly expand into the wall.

10. A sleeve bolt as defined in claim 9, wherein said tab means is adapted, once having displaced past said proximal end portion of said opening means, to lodge in a proximal portion of said slit and maintain said expansion wedge engaged to the wall .

11. A sleeve bolt as defined in claims 8 to 10, wherein two diametrically opposed opening means are defined in said expansion wedge, a pair of tabs extending outwardly from a proximal end of said threaded member being engaged in said opening means, said slit extending through one of said opening means .

12. A sleeve bolt as defined in claim 7, wherein said distal threaded member comprises a tab means extending into said opening means, said tab means being capable of displacing along said opening means, upon sufficient rotation of said stem and once said expansion wedge is substantially stationary onto said expander means, said opening means being closed at a proximal end thereof .

13. A sleeve bolt for insertion in a hole delimited by a wall, comprising a threaded fastener and an expansion means, said threaded fastener having a stem, said stem including a proximal stem section and a distal threaded section, said proximal stem section being provided at a distal end thereof with an expander means, said expansion means being adapted to be threadably engaged onto said distal threaded section and having a proximal end adapted, upon axial displacement of said expansion means towards said proximal stem section resulting from a rotation of said stem, to engage said expander means such to expand outwardly into engagement with the wall.

14. A sleeve bolt as defined in claim 13, wherein said expansion means comprise a distal threaded member and a proximal expansion wedge, said threaded member being adapted to be threadably engaged to said threaded section of said stem, said expansion wedge being adapted to frictionally engage the wall upon introduction of said stem in the hole while said threaded member is spaced from the wall such that, upon sufficient subsequent rotation of said stem, said expansion means displace towards said expander means .

15. A sleeve bolt as defined in claim 14, wherein a transversal size of said expander means reduces in direction of said distal threaded section of said stem such that, upon displacement of said expansion wedge along said distal threaded section and towards said expander means, a proximal end of said expansion wedge engages said expander means and gradually expands outwardly.

16. A sleeve bolt as defined in claims 14 and 15, wherein said threaded member of said expansion means comprises a conical section which tapers towards said expansion wedge, said conical section being adapted, upon sufficient rotation of said stem and once said expansion wedge is substantially stationary onto said expander means, to displace towards and relative to both said expander means and said expansion wedge such that said conical section causes a distal end of said expansion wedge to expand outwardly into engagement with the wall .

17. A method of setting a sleeve bolt in a hole delimited by a wall, comprising the steps of: (a) providing a threaded fastener and an expansion means threadably engaged to a distal end of said fastener;

(b) inserting said expansion means and part of said threaded fastener in the hole,- (c) rotating sufficiently said fastener with said expansion means being frictionally engaged to the wall for causing said expansion means to displace towards a proximal end of said fastener and for causing a proximal end of said expansion means to be expanded by said fastener into engagement with the wall .

18. A method as defined in claim 17, wherein said fastener has a stem, said stem including a proximal stem section and a distal threaded section, said proximal stem section having substantially a diameter of the hole and being provided at a distal end thereof with an expander means for expanding said expansion means in step c) , said expansion means being adapted to be threadably engaged onto said distal threaded section and having a proximal end adapted, upon axial displacement of said expansion means towards said proximal stem section resulting from a rotation of said stem, to engage said expander means such to expand outwardly into engagement with the wall.

19. A method as defined in claim 18, wherein said expansion means comprise a distal threaded member and a proximal expansion wedge, said threaded member being adapted to be threadably engaged to said threaded section of said stem, said expansion wedge being adapted to frictionally engage the wall upon introduction of said stem in the hole while said threaded member is spaced from the wall such that, upon sufficient subsequent rotation of said stem, said expansion means displace towards said expander means .

20. A method as defined in claim 19, wherein a transversal size of said expander means reduces in direction of said distal threaded section of said stem such that, upon displacement of said expansion wedge along said distal threaded section and towards said expander means, a proximal end of said expansion wedge engages said expander means and gradually expands outwardly.

21. A method as defined in claim 20, wherein said expander means defines a taper.

22. A method as defined in claim 21, wherein said expander means comprises a frusto-conical portion.

23. A method as defined in claims 19 to 22, wherein said threaded member of said expansion means comprises a conical section which tapers towards said expansion wedge, said conical section being adapted, upon sufficient rotation of said stem and once said expansion wedge is substantially stationary onto said expander means, to displace towards and relative to both said expander means and said expansion wedge such that said conical section causes a distal end of said expansion wedge to expand outwardly into engagement with the wall.

24. A method as defined in claims 19 to 23, wherein said expansion wedge defines at least one opening means, said distal threaded member of said expansion means being engaged in said opening means such that said expansion wedge and said distal threaded member rotate jointly with respect to said stem.

25. A method as defined in claim 24, wherein said distal threaded member comprises a tab means extending into said opening means, said tab means being capable of displacing along said opening means, upon sufficient rotation of said stem and once said expansion wedge is substantially stationary onto said expander means, and of causing said expansion wedge to expand outwardly.

26. A method as defined in claim 25, wherein said expansion wedge defines a longitudinal slit extending along a whole length thereof and through said opening means, said opening means comprising a proximal end portion tapering in direction of expander means, whereby said tab means, upon engaging said proximal end portion of said opening means, cause said expansion wedge to gradually outwardly expand into the wall.

27. A method as defined in claim 26, wherein said tab means is adapted, once having displaced past said proximal end portion of said opening means, to lodge in a proximal portion of said slit and maintain said expansion wedge engaged to the wall .

28. A method as defined in claims 25 to 27, wherein two diametrically opposed opening means are defined in said expansion wedge, a pair of tabs extending outwardly from a proximal end of said threaded member being engaged in said opening means, said slit extending through one of said opening means.

29. A method as defined in claim 24, wherein said distal threaded member comprises a tab means extending into said opening means, said tab means being capable of displacing along said opening means, upon sufficient rotation of said stem and once said expansion wedge is substantially stationary onto said expander means, said opening means being closed at a proximal end thereof .