HK1243155B - Anchor having a wave-shaped sleeve - Google Patents

Description

Anchor bolt with a corrugated sleeve

Technical Field

The invention relates to an anchor bolt comprising a sleeve, a bolt shank extending through the sleeve, and at least one expansion element axially upstream of the sleeve and axially supported on the sleeve, wherein the bolt shank has an expansion region for the expansion element.

Background Art

DE 202009013641 U1 shows a post-cut anchor for fixing a facade panel made of natural stone to a base structure. The anchor has a corrugated, closed expansion ring as an expansion element.

DE 102007060956 A1 discloses an expansion anchor for connecting a stone slab to a concrete slab. The expansion anchor comprises an expandable element that can be expanded by being pushed onto an expansion body. The expansion anchor also comprises a force transmission element through which the force for pushing the expandable element onto the expansion body can be transmitted. The force transmission element is stiffer in the force transmission direction than in a direction transverse to the force transmission direction. For example, the force transmission element can be a sleeve having a cylindrical central bore and a circumferentially corrugated outer circumference.

DE 8416683 U1 shows an expansion pin having a plastic sleeve as a pressing region, which has outer longitudinal ribs as anti-rotational means. DE 102006053226 A1 discloses a further pressable sleeve having outer ribs.

DE102004010727 A1 shows an expansion anchor in which expansion lugs are provided as expansion elements, which are separated by a slot. On the edges of the expansion lugs formed at the slot, the expansion elements extend tangentially to the longitudinal axis of the anchor, that is, they protrude outward there.

EP 2848825 A1 proposes providing an expansion element designed as an expansion lug with at least one rib that projects into the interior of the sleeve and forms a local increase in wall thickness, and providing a corresponding recess in the bolt shaft that at least partially accommodates the rib before the expansion lug is expanded. Due to the local increase in wall thickness at the rib, a particularly large maximum radial expansion of the expansion element can be achieved during expansion, thereby achieving particularly good anchoring.

DE 19538898 C2 discloses a percussion anchor with an additional expansion sleeve. This expansion sleeve has ribs that are radially guided through the pin body. When installing the percussion anchor, a striking tool is placed against the ribs, and the action of the striking tool pushes the expansion sleeve axially forward onto the ribs. For stability, the ribs arranged inside the pin body can be of corrugated design.

DE 3336168 C2 discloses a tensioning pin in which grooves can be provided on the outer surface of the tensioning region of the tensioning pin. These grooves prevent the tensioning pin from being easily pulled out of the masonry because the grooves create a higher coefficient of friction. Alternatively, a wave-like structure with a corrugated structure can be provided instead of the grooves, which surrounds the pin in an annular manner.

US Pat. No. 4,753,559 A shows a double-shell expansion sleeve for a rock anchor, which has a corrugation with a corrugated structure which surrounds the expansion sleeve in an annular manner.

Summary of the Invention

The object of the present invention is to provide an anchor which is particularly advantageous in terms of production while being highly reliable and easy to use and which at the same time has particularly good load values, preferably also under transverse loads.

According to the invention, this object is achieved by an anchor having the following features. Preferred embodiments are given below.

Specifically, the present invention provides an anchor bolt comprising a sleeve, a bolt rod passing through the sleeve, and at least one expansion element, wherein the at least one expansion element is located axially in front of the sleeve and is axially supported on the sleeve, wherein the bolt rod has an expansion area for the expansion element, and is characterized in that the sleeve has a waveform comprising axially extending wave crests and axially extending wave troughs, wherein the outer radius of the sleeve and the inner radius of the sleeve each have a maximum value in the wave crests, and the outer radius of the sleeve and the inner radius of the sleeve each have a minimum value in the wave troughs; and the waveform extends to the rear side of the sleeve facing away from the expansion element.

The present invention further provides an anchor bolt comprising a sleeve, a bolt rod passing through the sleeve, and at least one expansion element, wherein the at least one expansion element is located axially in front of the sleeve and is axially supported on the sleeve, wherein the bolt rod has an expansion area for the expansion element, and is characterized in that the sleeve has a waveform comprising axially extending wave crests and axially extending wave troughs, wherein in the wave crests, the outer radius of the sleeve and the inner radius of the sleeve each have a maximum value, and in the wave troughs, the outer radius of the sleeve and the inner radius of the sleeve each have a minimum value; and the waveform covers the entire sleeve.

The present invention further provides an anchor bolt comprising a sleeve, a bolt rod extending through the sleeve, and at least one expansion element, wherein the at least one expansion element is located axially in front of the sleeve and is axially supported on the sleeve, wherein the bolt rod has an expansion area for the expansion element, and is characterized in that the sleeve has a waveform comprising axially extending wave crests and axially extending wave troughs, wherein the outer radius of the sleeve and the inner radius of the sleeve each have a maximum value in the wave crests, and the outer radius of the sleeve and the inner radius of the sleeve each have a minimum value in the wave troughs; the waveform extends to the rear side of the sleeve facing away from the expansion element and covers the entire sleeve.

The present invention further provides an anchor bolt comprising a sleeve, a bolt rod passing through the sleeve, and at least one expansion element, wherein the at least one expansion element is located axially in front of the sleeve and is axially supported on the sleeve, wherein the bolt rod has an expansion area for the expansion element, characterized in that the sleeve has a waveform comprising axially extending wave crests and axially extending wave troughs, wherein in the wave crests, the outer radius of the sleeve and the inner radius of the sleeve each have a maximum value, and in the wave troughs, the outer radius of the sleeve and the inner radius of the sleeve each have a minimum value; and the at least one expansion element is an expansion lug, which is located axially in front of the wave crests.

The present invention further provides an anchor bolt comprising a sleeve, a bolt rod extending through the sleeve, and at least one expansion element, wherein the at least one expansion element is located axially in front of the sleeve and is axially supported on the sleeve, wherein the bolt rod has an expansion area for the expansion element, characterized in that the sleeve has a corrugation comprising axially extending wave crests and axially extending wave troughs, wherein in the wave crests, the outer radius of the sleeve and the inner radius of the sleeve each have a maximum value, and in the wave troughs, the outer radius of the sleeve and the inner radius of the sleeve each have a minimum value; the anchor bolt has a plurality of expansion elements configured as expansion lugs, wherein an expansion lug is arranged axially in front of each wave crest.

The anchor bolt according to the present invention is characterized in that the sleeve has a waveform including a wave crest extending in the axial direction and a wave trough extending in the axial direction, wherein the outer radius of the sleeve and the inner radius of the sleeve each have a maximum value in the wave crest, and the outer radius of the sleeve and the inner radius of the sleeve each have a minimum value in the wave trough.

The basic idea of the present invention may be that the sleeve has a wave pattern in which, viewed in the circumferential direction of the sleeve, wave crests and wave troughs alternate. The wave pattern is particularly present in phase (synchronously) both on the inside and on the outside of the sleeve, i.e., at the wave crests, both the inner radius and the outer radius of the sleeve are at their maximum, in particular, locally maximum, while at the wave troughs, both the inner radius and the outer radius of the sleeve are at their minimum, in particular, locally minimum.

Due to this corrugation, the sleeve according to the present invention can cover the same annular space as a sleeve made of solid material (volume), but with significantly less material consumption. In particular, the sleeve according to the present invention can form contact points for supporting the bolt on the sleeve at the wave troughs and contact points for supporting the sleeve on the borehole wall at the wave crests. Thus, according to the present invention, a particularly cost-effective sleeve can be obtained without significantly compromising functionality. Such a sleeve can preferably be manufactured, for example, from sheet metal using a deformation forming method, which further reduces manufacturing costs.

Furthermore, the corrugated sleeve according to the invention can improve the load values of the anchor bolt, in particular under transverse loads, which can occur, for example, in earthquakes. The corrugated shape according to the invention enables targeted deformation of the sleeve in the transverse direction, which (as will be explained in more detail below with reference to the figures) is advantageous with regard to transverse load bearing capacity, in particular because an axial force component can be generated instead of shear forces.

According to the invention, the troughs and crests extend axially, which may include, in particular, the case where, in axially spaced-apart cross-sectional planes of the sleeve, the crests and troughs each lie one above the other. In particular, the sleeve may at least partially have a constant cross-section along the sleeve, i.e., the radial extent of the crests and troughs does not vary along the longitudinal axis. In particular, the troughs and/or crests may extend parallel to the longitudinal axis.

The axial, radial and/or circumferential directions mentioned here are in particular the longitudinal axis of the shank, the sleeve and/or the anchor, wherein these axes preferably coincide. The outer and inner radii are also measured from this longitudinal axis.

Preferably, the waveform is periodic, which may include, in particular, the situation where wave crests and wave troughs repeat at regular intervals. This allows for a particularly high degree of symmetry, which may be advantageous with regard to force transmission.

The sleeve preferably surrounds the bolt in an annular manner. The expansion region can be provided, in particular, in the region of the front end of the bolt. The sleeve is preferably arranged on the bolt, at least partially offset rearward relative to the expansion region of the bolt. The bolt preferably has a load introduction region in the region of its rear end for introducing tensile forces into the bolt. For example, the load introduction region can be implemented as an external thread. However, it is also conceivable to implement the load introduction region as a bayonet screw mechanism or a simple head with a widened cross section.

In the expansion region of the bolt rod, a wedge-shaped drive is formed between the bolt rod and the expansion element. When axial tension acts on the bolt rod, this wedge-shaped drive can press the expansion element radially outward, thereby anchoring the anchor in the drilled hole. In particular, a bevel of the bolt rod can be provided in the expansion region, on which the radius of the bolt rod decreases toward the rear side of the bolt rod, i.e., the bevel widens toward the front side of the bolt rod. Preferably, the expansion region is an expansion cone. The anchor can, in particular, be an undercut anchor, which is anchored in an undercut drilled hole. In this case, the expansion element engages in the undercut portion of the drilled hole (i.e., the conically undercut portion of the hole) during anchoring. The anchor according to the present invention can preferably be used to fasten facade panels to a base structure.

The expansion element is supported axially on the sleeve. The sleeve can thus form a seat for the expansion element, preventing it from withdrawing rearwards when the expansion region of the bolt rod presses against the expansion element under tension in the bolt rod. The sleeve can in turn be supported on its rear side, for example, on a mounting element. This sleeve can also be referred to as a spacer sleeve, in particular to distinguish it from an expansion sleeve.

The bolt rod is preferably one-piece, in particular integral. However, it can also be multi-part, wherein in particular the load introduction region and the expansion region can be arranged on different parts of the bolt rod. The sleeve and/or the bolt rod are preferably made of a metal material, in particular steel.

In particular, it can be provided that the height of the sleeve is at least 0.5 times as large as its circumferential diameter, preferably at least 1 times as large as its circumferential diameter. For tall sleeves, the material saving effect according to the invention is particularly significant.

In order for the corrugation to function particularly effectively, the difference in the inner diameter of the sleeve between a wave crest and an adjacent wave trough is preferably at least partially at least 0.5 times, in particular at least 1 times, the wall thickness of the sleeve in this local area. For the same reason, the difference in the outer diameter of the sleeve between a wave crest and an adjacent wave trough is preferably at least partially at least 0.5 times, in particular at least 1 times, the wall thickness of the sleeve in this local area. The peak-to-trough distance is therefore at least 0.5 times the wall thickness.

It is particularly advantageous if the sleeve has a constant wall thickness over at least 75% of its surface, preferably at least 90%. This can be advantageous in terms of production, since sheet metal can be used as the starting material. It can also be advantageous in terms of force transmission. Deviations from this constant wall thickness can be provided, for example, by local hook elements that anchor the sleeve to the borehole wall. In accordance with conventional methods in the art, this constant wall thickness can include fluctuations of no more than ±3% of the wall thickness.

Furthermore, it is advantageous if the wave pattern extends to its limit on the sleeve, that is, to the rear side of the sleeve facing away from the expansion element. This ensures that the wave pattern of the anchored bolt reaches a position particularly close to the drill hole opening, which can be advantageous in terms of load bearing capacity. It is particularly preferred that the wave pattern covers the entire sleeve, so that the wave crests and troughs extend along the entire sleeve, from its front side to its rear side. Such a sleeve can be manufactured particularly easily and also serves to achieve particularly good centering in the drill hole.

The at least one expansion element can be, for example, a ring made of (metal) wire, which surrounds the bolt. However, it is particularly advantageous if the at least one expansion element is an expansion lug. An expansion lug (Spreizlappen, expansion flap) can be understood in particular as an element that is flatly expanded (to a certain size) not only in the circumferential direction but also in the axial direction. The expansion lug preferably spans a maximum of one-quarter of the circumference of the bolt, that is, the angular expansion dimension of the expansion lug measured on the longitudinal axis is preferably less than 90°. This makes it possible to achieve particularly reliable expansion and particularly uniform force introduction, especially when a plurality of such expansion lugs are provided. The expansion lug can have one or more radially extending recesses, preferably through-holes, for example for targeted influence on the bending properties.

It is particularly advantageous for the expansion lug to be located axially in front of the wave crest. This can include, in particular, the following situations: the expansion lug and the wave crest span a common angular region along the longitudinal axis, that is, the expansion lug and the wave crest at least partially overlap when viewed along the longitudinal axis, and, on the other hand, the expansion lug is at least partially located axially in front of the wave crest. Thus, the expansion lug at least partially forms an extension of the wave crest and/or is at least partially aligned with the wave crest. Because the wave crest is located relatively far radially outward, according to this embodiment, the expansion lug is also located relatively far radially outward and can therefore achieve particularly effective pressure against the borehole wall even with a small bending angle caused by the expansion region. This results in a particularly reliable anchoring with minimal manufacturing effort.

In particular, it can be provided that the anchor has a plurality of expansion elements designed as expansion lugs, wherein an expansion lug is arranged axially in front of each wave crest. This additionally enables particularly uniform force transmission. If a plurality of expansion lugs are provided, at least one of these expansion lugs (preferably all of them) can be designed and implemented as described above in connection with a single expansion lug. The expansion lugs can together form an expansion sleeve, but this is not required.

Another preferred embodiment of the present invention provides for the at least one expansion element to be integrally formed with the sleeve. This integral connection of the expansion element and sleeve provides an anchor bolt that is particularly easy to handle. In particular, it can be provided that the at least one expansion element is integrally formed with the sleeve, wherein this integral design can include, in particular, the expansion element and sleeve being joined together without any joints. This further improves the anchoring reliability of the anchor bolt while simplifying production, in particular because the expansion element is positioned particularly reliably.

Furthermore, it is particularly advantageous if an axially extending slot is provided in the sleeve, which divides the sleeve. The slot divides the sleeve, that is, it extends from the front side of the sleeve to the rear side. As a result, the sleeve surrounds the bolt in a C-shaped manner. This design allows for particularly simple production of the sleeve from a sheet metal strip.

It is expedient if the slots are arranged in the wave troughs. This can further simplify production and further even out the introduction of force, in particular when the expansion element is located axially in front of all wave crests.

Another advantageous refinement of the present invention is that at least one projection is provided on the bolt, which engages in the sleeve and forms an anti-twist mechanism at the wave crest. The projection thus engages in the wave crest on the inner side of the sleeve and thereby secures the sleeve in a form-fitting manner against rotation relative to the bolt about the longitudinal axis. The wave shape can thus also function as an anti-twist mechanism in a particularly simple manner. Preferably, the projection is an axially extending rib. This allows for an axially extending form-fit and, therefore, a particularly reliable anti-twist effect. Advantageously, a plurality of projections, in particular axially extending ribs, are provided on the bolt at intervals in the circumferential direction, which engage in the sleeve and form an anti-twist mechanism at the corresponding wave crest.

In particular, it can be provided that the projection is arranged on the bolt at least partially offset axially rearward relative to the expansion region. The expansion region can thus remain free of bulges that could potentially negatively influence the expansion behavior by preventing axial movement in the event of an incorrect sleeve position. This embodiment further increases reliability in a particularly simple manner.

Another preferred embodiment of the present invention provides for the sleeve to taper forward. This taper can be provided, in particular, at the wave crests, that is, the wave crests extend gradually forward toward the longitudinal axis. With this design, diameter deviations in the drilled hole can be compensated for in a particularly simple manner, and a particularly good fit in the drilled hole can be achieved. Preferably, the sleeve tapers conically forward. This can include, in particular, the case where the wave crests define the generatrix of a cone.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described in detail below based on preferred embodiments, which are schematically shown in the accompanying drawings. Within the scope of the present invention, the various features of the embodiments shown below can in principle be implemented individually or in any combination. The accompanying drawings schematically show:

FIG1 is a perspective view of an anchor bolt according to the present invention;

FIG2 is another perspective view of the anchor bolt of FIG1 , wherein the anchor bolt is arranged in a drilled hole in a substrate in the situation of FIG2 ;

FIG3 is a view of the sleeve of the anchor bolt of FIG1 and FIG2 as seen from above;

FIG4 is a longitudinal sectional view of the anchor bolt of FIG1 and FIG2;

5 and 6 are the anchor bolts of FIGS. 1 and 2 under transverse load, shown in FIG. 5 in cross section at the height of the sleeve and in FIG. 6 in longitudinal section; and

7 and 8 are variations of the anchor bolt of FIGS. 1 and 2 , shown in FIG. 7 in cross section at the level of the sleeve and in FIG. 8 in side view.

Elements having the same effect are provided with the same reference numerals in the figures.

DETAILED DESCRIPTION

1 to 6 show an embodiment of an anchor bolt according to the invention. The anchor bolt comprises an elongated shank 10 which, in the region of its rear end, comprises a load introduction region 19 designed as an external thread and, in the region of its front end, comprises an at least approximately conical widening region 15 in which the cross section of the shank 10 increases towards the front.

The anchor bolt also has a sleeve 20, which annularly surrounds the bolt 10. A plurality of, for example, six, expansion elements 30 are arranged on the front side of the sleeve 20. These expansion elements 30 are designed as expansion lugs in the form of cylindrical shell segments and are integrally formed with the sleeve 20. The expansion elements 30 are arranged at least approximately equidistantly around the bolt 10. As shown in particular in FIG. 1 , the expansion elements 30 each have a recess, designed as a through-hole 31, at their transition to the sleeve 20, by means of which the bending properties can be adjusted.

In conventional use of the anchor shown in FIG2 , the anchor is introduced into a drilled hole in a substrate 9 with its front side leading. If a tensile force now occurs in the bolt shank 10, the expanded region 15 of the bolt shank 10 is pulled axially into the expansion element 30. Because the bolt shank 10 expands forward at the expanded region 15, the tensile force in the bolt shank 10 is converted into a radial force component on the expansion element 30, pressing the expansion element 30 against the wall 98 of the drilled hole and anchoring the anchor in the substrate 9. The sleeve 20 forms an axial support for the expansion element 30, which prevents it from being withdrawn rearward. The sleeve 20 is in turn secured in reverse on its rear side 71 by a mounting element 8, which is shown only in FIG6 .

The sleeve 20 has a corrugated shape comprising a plurality of wave crests 21 and wave troughs 22, which alternate along the circumference of the sleeve 20. The wave crests 21 and wave troughs 22 each extend axially along the sleeve 20, that is, in the direction of the longitudinal axis 99. The wave crests 21 and wave troughs 22 cover the entire sleeve 20 and extend in particular to the rear side 71 of the sleeve 20. As can be seen particularly in FIG. 3 , at the wave crests 21, both the inner radius _ri and the outer radius _ra of the sleeve 20, measured from the longitudinal axis 99, each have a local maximum. Conversely, at the wave troughs 22, both the inner radius _ri and the outer radius _ra of the sleeve 20 each have a local minimum. The wall thickness d of the sleeve 20 is substantially constant across the corrugated shape.

The expansion elements 30 are each located in front of a wave crest 21 and are axially aligned with the wave crest 21. In particular, the inner radius _ri and the outer radius _ra of each expansion element 30 are connected to the respectively adjacent wave crest 21. This can be seen in particular in FIG. 3 .

The sleeve 20 has a slot 28 which extends axially through the entire sleeve 20 and divides the sleeve 20. The sleeve 20 thus has a C-shape which encloses the bolt 10. The slot 28 is arranged in the wave trough 22 and is therefore offset in the circumferential direction relative to the expansion element 30.

As shown in particular in FIG. 4 , the sleeve 20 has a shape that tapers slightly forward, that is, toward the widened region 15 of the bolt 10. This taper, which can be particularly conical, is present in particular at the wave crest 21, that is, the wave crest 21 extends gradually forward toward the longitudinal axis 99. This tapering shape and the wave shape of the sleeve 20 allow it to be self-centered, especially even in non-perfectly circular boreholes. The angle α of the taper is preferably less than 10°, in particular less than 5°.

As shown in particular in FIG. 3 , the peak-to-valley distance—that is, the difference between the inner radius _ri of the sleeve 20 and/or the outer radius _ra of the sleeve 20 between a wave crest 21 and an adjacent wave trough 22—is greater than the wall thickness d. Due to the corrugation, the sleeve 20 can be supported not only on the wall 98 of the borehole, i.e., at the wave crests 21, but also on the bolt 10, i.e., at the wave troughs 22, while the annular gap between the bolt 10 and the borehole wall 98 is greater than the wall thickness d of the sleeve 20.

Furthermore, the corrugation can achieve exceptional load characteristics under transverse loads (e.g., caused by earthquakes). This is particularly illustrated in Figures 5 and 6. These figures show a situation in which a transverse load is applied to the bolt 10 via the mounting member 8. In this case, the region of the corrugation located in front of the bolt 10 in the direction of the transverse load (the lower portion of Figure 5) is flattened by the bolt 10. This allows for a certain degree of deformation under seismic loads, which can lead to improved load characteristics compared to a rigid, non-flexible sleeve.

In particular, a deformation of the sleeve 20, as shown in FIG6 , can lead to a slight tilting of the bolt 10 (towards the left in FIG6 ), which pulls the expanded region 15 axially toward the sleeve 20 on the side facing away from the transverse load direction (to the right in FIG6 ), and thus loads the anchor bolt in the main load direction. Transverse loads that would otherwise act transversely to the main load direction can be converted into a load component in the main load direction by this mechanism.

Figures 7 and 8 show a variant of the anchor bolt of Figures 1 to 6. According to this variant of Figures 7 and 8, the bolt shank 10 has radially outwardly projecting projections 11, which are embodied as ribs extending axially and parallel to one another. Each projection 11 engages internally in a wave crest 21 and thus couples the sleeve 20 and bolt shank 10 to one another in a rotationally fixed manner. In other words, they form a torsion lock between the sleeve 20 and the bolt shank 10. As shown in particular in Figure 8, the projections 11 are offset axially rearward relative to the expansion region 15, that is, toward the load introduction region 19, so that they do not hinder the expansion process of the expansion element 30.

Claims (28)

1. An anchor bolt, said anchor bolt being a back-cut anchor bolt and comprising a sleeve (20), a bolt shank (10) passing through the sleeve (20), and at least one expansion element (30), said at least one expansion element being axially positioned prior to the sleeve (20) and said at least one expansion element being axially supported on the sleeve (20), wherein the bolt shank (10) has an expansion region (15) for said expansion element (30), characterized in that, The sleeve (20) has a waveform comprising axially extending crests (21) and axially extending troughs (22), wherein the outer radius (ra) and inner radius ( _ri ) of the sleeve (20) are both at maximum values in the crests, and the outer radius (ra) and inner radius ( _{ri )} of the sleeve (20) are both at minimum values in the troughs; the waveform covers the entire sleeve (20), wherein the troughs and _crests extend parallel to the longitudinal axis, and the radial extension dimensions of the crests and troughs do not change along the longitudinal axis. 2. The anchor bolt as claimed in claim 1, wherein the sleeve (20) has a constant wall thickness (d). 3. The anchor bolt as claimed in claim 1, wherein the sleeve (20) has a constant wall thickness (d) over at least 90% of its surface. 4. The anchor bolt according to any one of claims 1 to 3, characterized in that the at least one expansion element (30) is an expansion lug located axially before the crest (21). 5. The anchor bolt according to any one of claims 1 to 3, characterized in that the anchor bolt has a plurality of expansion elements (30) configured as expansion lugs, wherein expansion lugs are arranged axially before each crest (21). 6. The anchor bolt according to any one of claims 1 to 3, characterized in that the at least one expansion element (30) and the sleeve (20) are constructed as a single piece. 7. The anchor bolt according to any one of claims 1 to 3, characterized in that an axially extending slot (28) is provided in the sleeve (20) to separate the sleeve (20), wherein the slot (28) is arranged in a trough (22). 8. The anchor bolt according to any one of claims 1 to 3, characterized in that at least one protrusion (11) is provided on the bolt rod (10), the at least one protrusion engaging in the sleeve (20) to form an anti-torsion mechanism at the crest (21). 9. The anchor bolt as claimed in claim 8, wherein the protrusion (11) is arranged on the bolt rod (10) in an axially rearward offset relative to the expansion region (15). 10. The anchor bolt according to any one of claims 1 to 3, characterized in that the sleeve (20) gradually tapers forward. 11. The anchor bolt according to any one of claims 1 to 3, characterized in that the waveform extends to the rear side (71) of the sleeve (20) opposite to the expansion element (30). 12. An anchor bolt, the anchor bolt being a back-cut anchor bolt and comprising a sleeve (20), a bolt shank (10) passing through the sleeve (20), and at least one expansion element (30), the at least one expansion element being axially positioned prior to the sleeve (20) and axially supported on the sleeve (20), wherein the bolt shank (10) has an expansion region (15) for the expansion element (30), characterized in that, The sleeve (20) has a waveform including an axially extending crest (21) and an axially extending trough (22), in which the outer radius (ra) and inner radius ( _ri ) of the sleeve (20) are both at their maximum values, and in the trough, the outer radius ( _{ra) and inner radius (ri )} of the sleeve (20) are both at their minimum values, wherein the trough and the _crest extend parallel to the longitudinal axis, and the radial expansion dimension of the crest and the trough does not change along the longitudinal axis; the at least one expansion element (30) is an expansion lug located axially before the crest (21). 13. The anchor bolt as claimed in claim 12, wherein the sleeve (20) has a constant wall thickness (d). 14. The anchor bolt as claimed in claim 12, wherein the sleeve (20) has a constant wall thickness (d) over at least 90% of its surface. 15. The anchor bolt according to any one of claims 12 to 14, characterized in that the anchor bolt has a plurality of expansion elements (30) configured as expansion lugs, wherein expansion lugs are arranged axially before each crest (21). 16. The anchor bolt according to any one of claims 12 to 14, characterized in that the at least one expansion element (30) and the sleeve (20) are constructed as a single piece. 17. The anchor bolt according to any one of claims 12 to 14, characterized in that an axially extending slot (28) is provided in the sleeve (20) to separate the sleeve (20), wherein the slot (28) is arranged in a trough (22). 18. The anchor bolt according to any one of claims 12 to 14, characterized in that at least one protrusion (11) is provided on the bolt rod (10), the at least one protrusion engaging in the sleeve (20) to form an anti-torsion mechanism at the crest (21). 19. The anchor bolt as claimed in claim 18, wherein the protrusion (11) is arranged on the bolt rod (10) in an axially rearward offset relative to the expansion region (15). 20. The anchor bolt according to any one of claims 12 to 14, characterized in that the sleeve (20) gradually tapers forward. 21. An anchor bolt, the anchor bolt being a back-cut anchor bolt and comprising a sleeve (20), a bolt shank (10) passing through the sleeve (20), and at least one expansion element (30), the at least one expansion element being axially positioned prior to the sleeve (20) and axially supported on the sleeve (20), wherein the bolt shank (10) has an expansion region (15) for the expansion element (30), characterized in that, The sleeve (20) has a waveform including axially extending crests (21) and axially extending troughs (22), in which the outer radius (ra) and inner radius ( _ri ) of the sleeve (20) are both at maximum values, and in the troughs, the outer radius ( _ra ) and inner radius ( _ri ) of the sleeve (20) are both at minimum values, wherein the troughs and the _crests extend parallel to the longitudinal axis, and the radial expansion dimensions of the crests and the troughs do not change along the longitudinal axis; the anchor bolt has a plurality of expansion elements (30) configured as expansion lugs, wherein an expansion lug is arranged axially before each crest (21). 22. The anchor bolt as claimed in claim 21, wherein the sleeve (20) has a constant wall thickness (d). 23. The anchor bolt as claimed in claim 21, wherein the sleeve (20) has a constant wall thickness (d) over at least 90% of its surface. 24. The anchor bolt according to any one of claims 21 to 23, characterized in that the at least one expansion element (30) and the sleeve (20) are constructed as a single piece. 25. The anchor bolt according to any one of claims 21 to 23, characterized in that an axially extending slot (28) is provided in the sleeve (20) to separate the sleeve (20), wherein the slot (28) is arranged in a trough (22). 26. The anchor bolt according to any one of claims 21 to 23, characterized in that at least one protrusion (11) is provided on the bolt rod (10), the at least one protrusion engaging in the sleeve (20) to form an anti-torsion mechanism at the crest (21). 27. The anchor bolt as claimed in claim 26, wherein the protrusion (11) is arranged on the bolt rod (10) in an axially rearward offset relative to the expansion region (15). 28. The anchor bolt according to any one of claims 21 to 23, characterized in that the sleeve (20) gradually tapers forward.