Expansion anchor with adaptive annular groove on expansion sleeve

Abstract

The invention relates to an expansion anchor comprising an anchor bolt and an expansion sleeve surrounding the anchor bolt, an expansion body arranged on the anchor bolt for the expansion sleeve, the expansion body being arranged at least partially in front of the expansion sleeve, the expansion sleeve has a first annular groove on its outer face in the front region of the expansion sleeve, the first annular groove having a front side and a rear side. According to the invention, at least in at least one radial plane, the angle of inclination of the rear side of the first annular groove differs by less than 8 DEG from the angle of inclination of the expansion body in the opposite region of the expansion body.

Description

[0001] This invention application is a divisional application of Chinese patent application CN201880072469.2.

[0002] This patent application claims priority to European patent application EP 17207901.4, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to an expansion anchor according to the preamble of claim 1. Such an expansion anchor is provided with an anchor bolt and an expansion sleeve surrounding the anchor bolt, an expansion body disposed on the anchor bolt for expanding the sleeve, the expansion body being at least partially disposed in front of the expansion sleeve, and the expansion sleeve having a first annular groove on its outer surface in the front region of the expansion sleeve, the first annular groove having a front side and a rear side. Background Technology

[0004] General document CA 2979509 A1 discloses an expansion sleeve for an expansion anchor, the expansion sleeve having an annular groove and a forward-opening annular step on its outer surface.

[0005] DE 102004053255 A1 describes an expansion anchor with an expansion sleeve having a reduced wall thickness and reduced external dimensions on the front edge facing the expansion body.

[0006] EP 2029900 A2 discloses an expansion anchor having a plurality of annular grooves in an expansion sleeve. EP 0308619A1 describes an expansion anchor having an expansion sleeve having cutting teeth and annular grooves on its outer surface. EP0365475 A2 describes an anchor in which the expansion sleeve has a bevel and a first annular groove spaced apart therefrom on its end face.

[0007] Another expansion anchor is disclosed in DE 2046341 A1, wherein an annular step that opens on the end face is provided in the expansion sleeve to receive a retaining ring. Summary of the Invention

[0008] The object of this invention is to provide an expansion anchor that is particularly effective and has particularly good load-bearing capacity, while requiring minimal production costs and having high reliability.

[0009] According to the present invention, the problem is solved by an expansion anchor having the features of claim 1. Preferred embodiments are specified in the dependent claims.

[0010] An expansion anchor according to the invention is characterized in that, in at least one radial plane, the inclination angle of the rear side of the first annular groove differs from the inclination angle of the expansion body in the opposite region of the expansion body by less than 8°, preferably less than 6° or less than 4°. This is particularly true for at least the rear side of the first annular groove, preferably in a state of rearward displacement relative to the opposite region in at least one radial plane of the entire first annular groove, i.e., specifically in the state before the expansion anchor is assembled. Therefore, (β) 61 =α 27 ±8°), (β) 61 =α 27 ±6°) or (β) 61 =α 27 ±4°), where β 61 It is the inclination angle α of the rear side of the first annular groove. 27 It is the tilt angle of the expansion body in the opposite region.

[0011] The basic concept of the invention can be considered as designing the rear side of the first annular groove as a mirror image of the expansion body in its opposite region. Therefore, the rear side can form at least a nearly horizontal region upon entering the expansion body, such that the region of the expansion sleeve in front of the first annular groove can be particularly prominently protruded upon entering the expansion body, for example, by an annular protrusion arranged there. This, in turn, allows for particularly good anchoring to the borehole wall, preferably by forming at least one undercut and rigidly engaging with said undercut, with particularly minimal outlay and particularly good residual wall thickness, and thus good tensile strength of the expansion sleeve. It has been shown that particularly good load values ​​can also be obtained even when the edge layer of the borehole is damaged. Since the slippage of the expansion sleeve is effectively counteracted, the assembly depth and therefore the concrete capacity can also be utilized particularly well.

[0012] An expansion body, as part of the expansion anchor according to the invention, is configured to expand the expansion sleeve. The expansion body converges rearwardly, particularly on its outer surface; that is, the outer cross-section of the expansion body increases forward. The expansion body may be conical, at least in the region, and thus may also be referred to as an expansion cone. If the expansion body is axially displaced rearward relative to the expansion sleeve, i.e., if the expansion body is drawn into the expansion sleeve, the expansion body can cause the expansion sleeve to expand radially to anchor in the borehole. The expansion body is at least partially arranged in front of the expansion sleeve; that is, at least a portion of the expansion body is axially located in front of the expansion sleeve. The expansion body is advantageously arranged in the front region of the anchor bolt.

[0013] The expansion sleeve, expansion body, and / or anchor bolt are preferably at least partially made of metallic material. Specifically, the expansion body is arranged on the anchor bolt in a tensile manner, so that backward tensile force can be transferred from the anchor bolt to the expansion body. The expansion body and the anchor bolt are preferably integral. However, the expansion body and the anchor bolt can also be separate components. Specifically, the expansion body can preferably be directly screwed onto the anchor bolt.

[0014] The anchor bolt may have a load-applying structure in its rear region. The load-applying structure is used to introduce tensile force into the anchor bolt. For example, the load-applying structure may be an external thread or an internal thread. In another embodiment, the load-applying structure may also be a head forming the maximum cross-section.

[0015] The expansion sleeve may have one or more expansion slots, preferably extending in the longitudinal direction, which divide the expansion sleeve into multiple expansion tabs and can penetrate the first annular groove, any other annular grooves that may exist, and / or annular steps that may exist. The front area of ​​the expansion sleeve faces the expansion body.

[0016] With regard to the axial and radial directions mentioned herein, this can specifically refer to the longitudinal axis of the anchor bolt, which can specifically coincide with the longitudinal axis of the expansion anchor. Different tilt angles should also be specifically related to the longitudinal axis of the anchor bolt. The longitudinal axis of the anchor bolt specifically extends in the assembly direction, i.e., in the direction in which the anchor bolt is inserted into the borehole during intended installation. Specifically, the tilt angle of the expansion body should be measured radially from the outside of the expansion body. Different widths should be understood particularly in the axial direction, and different depths should be understood particularly in the radial direction relative to the longitudinal axis of the anchor bolt. The directional indications “front” and “back” or “rear” are used uniformly here, especially when these directional indications are used in conjunction with the anchor bolt and expansion sleeve. Specifically, the directional indications are intended to refer to the axial direction. The radial plane here is specifically the radial plane relative to the longitudinal axis of the anchor bolt, i.e., in the conventional manner in the art, especially the plane containing the longitudinal axis of the anchor bolt. Specifically, the radial plane is the radial plane of the anchor bolt.

[0017] Specifically, the expansion sleeve and anchor bolt can be arranged coaxially.

[0018] The tilt angles of the expansion body in the opposite region and the tilt angle of the rear side of the first annular groove are both acute angles. The tilt angle of the expansion body in the opposite region opens forward, and the tilt angle of the rear side of the expansion body opens rearward. Since the opposite region and the rear side of the first annular groove correspond to each other at least approximately, and since the opposite region acts on the expansion sleeve from the inside (i.e., inside the sleeve) at the level of the rear side when the expansion anchor is used as intended, the opposite region can also be referred to as the lateral opposite region.

[0019] The inner surface of the expansion sleeve can be specifically understood as the surface facing the anchor bolt, while the outer surface of the expansion sleeve is the side facing away from the anchor bolt. The outer surface of the expansion body can be specifically understood as its side surface.

[0020] Specifically, the front side of the first annular groove faces rearward and the rear side faces forward. Preferably, at least one of the two sides of the first annular groove is designed to be tapered.

[0021] The first annular groove is formed, in particular, a radial recess in at least one radial plane, especially a recess relative to the majority of the outer surface of the expansion sleeve. The optional second annular groove and / or optional annular step are also preferably applicable. The first annular groove, the optional second annular groove, and / or the optional annular step extend about the longitudinal axis of the anchor bolt and / or in each case lie in a plane extending perpendicular to the longitudinal axis of the anchor bolt. The first annular groove, the optional second annular groove, and / or the optional annular step are arranged on the outer surface of the expansion sleeve, i.e., on the surface of the expansion sleeve opposite to the anchor bolt.

[0022] Unless otherwise stated, the features described herein are intended specifically to apply to unassembled expansion anchors, i.e., the state before assembly of the expansion anchor and / or expansion sleeve, before it has been expanded by the expansion body and / or at least the rear side of the first annular groove is axially displaced rearward relative to the expansion body. Specifically, when the expansion anchor is not assembled, the cross-section of the expansion sleeve may be less than or equal to the cross-sectional dimension of the expansion body. If the expansion body reaches the expansion sleeve under load and axial displacement, the expansion sleeve deforms in such a way as to protrude a raised edge that prevents axial displacement of the expansion sleeve in the borehole.

[0023] Specifically, the rear side of the first annular groove has a constant inclination angle in at least one radial plane. Specifically, the rear side of the first annular groove should have a significant axial length, such that the inclination angle of the rear side should not be understood as an angle along a tangent, but rather as an angle over an axially extending region.

[0024] In the opposite region, the expansion body has a constant tilt angle in at least one radial plane. The opposite region of the expansion body should have a significant axial length such that the tilt angle of the expansion body in the opposite region should not be understood as a tangential angle, but rather as an angle over an axially extending region. The opposite region of the expansion body is radially located on the outside of the expansion body and / or acts on the expansion sleeve to cause the expansion sleeve to expand radially. In the opposite region, the expansion body converges rearward, i.e., toward the expansion sleeve, in at least one radial plane. Specifically, the tilt angle of the expansion body in the opposite region is an acute angle, i.e., not a right angle. The rear side of the first annular groove converges forward toward the longitudinal axis of the anchor bolt in at least one radial plane.

[0025] Particularly preferred is the width w of the opposite region. 27 At least in at least one radial plane, at least with the width w of the rear side of the first annular groove 61 They are the same size. Therefore, w 61 ≤ w 27 This allows the expansion sleeve to follow the corresponding profile of the expansion body particularly well.

[0026] It has been recognized that the present invention can use particularly steep expansion bodies. This is because, according to the present invention, the protruding structures on the expansion sleeve can generate particularly significant external friction on the expansion anchor assembled on the expansion sleeve. However, this also increases internal friction on the expansion sleeve without pulling the expansion sleeve out of the borehole. Particularly preferably, the maximum tilt angle α of the expansion body is at least in at least one radial plane. max Greater than 10° or greater than 15°. This is advantageous for the load value.

[0027] In another preferred embodiment of the invention, the front side of the first annular groove is steeper than the rear side of the first annular groove in at least one radial plane. "Stiff" should be understood specifically in relation to the longitudinal axis of the anchor bolt and includes an angle of inclination relative to the longitudinal axis. This can further improve efficiency and / or anchoring on the borehole wall.

[0028] Furthermore, it is advantageous that the front side of the first annular groove is adjacent to the rear side of the first annular groove in at least one radial plane. Therefore, in particular, there is no intermediate cylindrical groove base. This can further improve efficiency and / or anchoring on the borehole wall. However, an intermediate cylindrical groove base can also be provided.

[0029] Preferably, the expansion sleeve has a front bevel on its inner surface in at least one radial plane. This allows for particularly good deformation properties. Particularly preferably, at least a portion of the first annular groove is displaced rearward relative to the bevel in at least one radial plane. Preferably, at least the rear side of the first annular groove is displaced rearward relative to the bevel in at least one radial plane. Therefore, a particularly large residual wall thickness of the expansion sleeve can be achieved, and thus premature rupture of the expansion sleeve can be counteracted particularly effectively. Specifically, it can be provided that the entire first annular groove is offset rearward relative to the bevel in at least one radial plane, which is particularly advantageous in terms of production and efficiency.

[0030] Furthermore, it is particularly advantageous that the expansion sleeve has at least one second annular groove on its outer surface, especially in the front region of the expansion sleeve, in front of the first annular groove. This can further improve anchoring. The two annular grooves preferably extend parallel to each other, which ensures particularly uniform force introduction and also offers advantages in production. Specifically, the second annular groove can be separated from the first annular groove by a first annular protrusion. The annular protrusion is preferably aligned at its apex with the area of ​​the expansion sleeve arranged behind the first annular groove, i.e., the distance between the apex of the annular protrusion and the longitudinal axis of the anchor bolt is the same as the distance between the area of ​​the expansion sleeve arranged behind the first annular groove.

[0031] Preferably, in at least one radial plane, the width of the second annular groove is smaller than the width of the first annular groove, which can further improve efficiency, anchoring and / or expansion performance.

[0032] Furthermore, it is particularly advantageous that the expansion sleeve has at least one annular step, which opens at its front, particularly in front of the first annular groove and preferably in front of a second annular groove, which may be present. The foremost annular step allows the structure arranged behind it to penetrate the borehole wall particularly effectively by minimizing the surface pressed against the borehole wall and / or by forming a lever. The annular step and the first annular groove preferably extend parallel to each other, which ensures a particularly uniform induction force and also provides advantages in production. Specifically, the annular step may be separated from the second annular groove by a second annular protrusion.

[0033] Furthermore, advantageously, in at least one radial plane, the depth of the first annular groove is at least 0.25 times, preferably at least 0.4 times, the residual wall thickness of the expansion sleeve in the first annular groove. The same applies to the second annular groove and / or the annular step. Thus, each annular groove and / or annular step has a significant depth. As a result, a particularly prominent external structure and therefore particularly effective anchoring can be achieved.

[0034] Anchor bolts may preferably have a sleeve stop that restricts axial displacement of the expansion sleeve away from the expansion body, i.e., rearward. In this case, the expansion anchor may be designed as a so-called bolt anchor. In this case, the expansion body may preferably be integral with the anchor bolt. However, the expansion sleeve may also extend to the load-applying structure of the anchor bolt. In this case, the expansion anchor may be designed as a so-called sleeve anchor. In particular, the expansion body may be designed separately from the anchor bolt, and the expansion body is connected to the anchor bolt via a threaded connection. The sleeve stop may preferably be formed of a ring. The sleeve stop may, for example, be formed on an annular shoulder extending around the outside of the anchor bolt.

[0035] The present invention also relates to the intended use of expansion anchors, and in particular, to intended assemblies of expansion anchors. Specifically, the present invention relates to the use of an expansion anchor according to the invention, wherein the expansion body is inserted particularly rearward into an expansion sleeve until, particularly in at least one radial plane, the expansion sleeve is located at the level of the rear side of a first annular groove, particularly extending axially horizontally onto the opposite region of the expansion body. Specifically, this includes inserting the expansion body particularly rearward into the expansion sleeve such that, at least in at least one radial plane, the rear side of the first annular groove and the opposite region of the expansion body at least partially overlap axially. Thus, mirror structures are superimposed and can be aligned in their sum.

[0036] The features explained in connection with the expansion anchor according to the invention can also be used in the use according to the invention, and conversely, the features explained in connection with the use according to the invention can also be used in the expansion anchor according to the invention. Attached Figure Description

[0037] The invention will now be explained in more detail with reference to the preferred embodiments schematically shown in the accompanying drawings. Within the context of this invention, the various features of the embodiments shown below can, in principle, be implemented individually or in any desired combination. In the accompanying drawings, the following are schematically shown: Figure 1 This is a side view of the expansion anchor according to the present invention; Figure 2 This is a side view of an anchor bolt without an expansion sleeve; Figure 3 This is a partial longitudinal cross-sectional view of the expansion anchor; Figure 4 This is a detailed longitudinal section view of the expansion anchor in the front area of ​​the expansion sleeve; Figure 5 Showing Figure 4 The view is shown, but without reference numerals for clarity; and Figure 6 This is a schematic longitudinal cross-sectional view of the expansion anchor in the front area after the expansion process is completed. Detailed Implementation

[0038] The accompanying drawings illustrate an embodiment of an expansion anchor according to the present invention. The expansion anchor has an anchor bolt 20 and an expansion sleeve 10, the expansion sleeve 10 surrounding the anchor bolt 20 in an annular manner. The anchor bolt 20 has a neck region 25 having at least a substantially constant cross-section. Adjacent to the neck region 25, the anchor bolt 20 has an expansion body 26 for the expansion sleeve 10 in front of the neck region 25 at its front end region, the expansion body being integral with the anchor bolt 20, for example. The expansion body 26 widens forward from the neck region 25 on its outer surface, i.e., the expansion body 26 converges rearward on its outer surface. The expansion sleeve 10 surrounds the neck region 25 of the anchor bolt 20. The expansion body 26 is arranged in front of the expansion sleeve 10.

[0039] The anchor bolt 20 also has a sleeve stop 22, for example in the form of an annulus, which restricts the axial movement of the expansion sleeve 10 toward the rear end of the anchor bolt 20, that is, the axial movement of the expansion sleeve 10 away from the expansion body 26. The sleeve stop 22 is formed on an annular shoulder 23 extending around the anchor bolt 20.

[0040] Anchor bolt 20 has a load-applying structure 34, shown here as, for example, an external thread, at its rear end region opposite expansion body 26, for introducing tensile force into anchor bolt 20. A nut (not shown) with a corresponding internal thread may be arranged on the external thread.

[0041] The expansion sleeve 10 has a plurality of expansion slots 13 extending from the front end face 19 of the expansion sleeve 10 facing the expansion body 26 into the expansion sleeve 10. Expansion tabs are formed between these expansion slots 13.

[0042] In the location Figure 1 , Figure 3 , Figure 4 , Figure 5 and Figure 6 In the front region of the expansion sleeve 10 located on the left-hand side, the expansion sleeve 10 has a first annular groove 60 on its outer surface, i.e., on the surface opposite to the anchor bolt 20 extending around the expansion sleeve 10. In front of the first annular groove 60, the expansion sleeve 10 has a second annular groove 70 extending around the expansion sleeve 10 on its outer surface. In front of the first annular groove 60 and in front of the second annular groove 70, the expansion sleeve 10 has an annular step 80 extending around the expansion sleeve 10 on its outer surface.

[0043] The first annular groove 60 has a rear side 61 facing forward and / or facing the expansion body 26 and a front side 62 facing rearward. The rear side 61 faces forward near the longitudinal axis 99 of the anchor bolt 20, and the front side 62 faces rearward near the longitudinal axis 99 of the anchor bolt 20. Each of the two sides 61 and 62 of the first annular groove 60 extends at an acute angle to the longitudinal axis 99 of the anchor bolt 20. The two sides 61 and 62 of the first annular groove 60 merge directly, i.e., there is no cylindrical groove base.

[0044] The second annular groove 70 has a cylindrical groove base, that is, it extends parallel to the longitudinal axis 99 of the anchor bolt 20, and the groove base is defined by a front side and a rear side. Each of the two sides of the second annular groove 70 extends at an acute angle to the longitudinal axis 99 of the anchor bolt 20.

[0045] The annular step 80 opens toward the front end face 19 of the expansion sleeve 10 and therefore has only a single side, namely the rear side, which in this case extends at a right angle to the longitudinal axis 99 of the anchor bolt 20. The base of the annular step 80 is generally cylindrical.

[0046] A first annular protrusion 67 is formed on the outside of the expansion sleeve 10 between the first annular groove 60 and the second annular groove 70, and a second annular protrusion 78 is formed on the outside of the expansion sleeve 10 between the second annular groove 70 and the annular step 80.

[0047] On its inner surface, i.e., on the surface facing the anchor bolt 20, the expansion sleeve 10 has a bevel 90 extending toward the front end face 19 of the expansion sleeve 10, and thus the wall thickness of the expansion sleeve 10 decreases forward toward the front end face 19. The bevel 90 faces the expansion body 26 of the anchor bolt 20, so that the expansion body 26 can act against the bevel 90. The bevel 90 axially overlaps with the second annular groove 70 and the annular step 80, and is axially offset relative to the first annular groove 60. At the axial level of the first annular groove 60, the inner surface of the expansion sleeve 10 extends substantially parallel to the longitudinal axis 99 of the anchor bolt 20, i.e., the inner surface of the expansion sleeve is cylindrical there.

[0048] Figure 4 and Figure 5 This is a longitudinal cross-sectional view passing through the longitudinal axis 99 of the anchor bolt 20, that is, a view in a radial plane starting from the longitudinal axis 99. In this radial plane, the first annular groove 60 has a radial measuring depth d. 60 and axial measurement width w 60 The second annular groove 70 has a radial measuring depth d 70 and axial measurement width w 70 The rear side surface 61 of the first annular groove 60 has an inclination angle β relative to the longitudinal axis 99. 61 and axial measurement width w 61At the apex between the two sides 61 and 62 of the first annular groove 60, the expansion sleeve 10 has a radially measured residual wall thickness d in the radial plane. 10 .

[0049] The expansion body 26 has, in particular, an axially extending opposing region 27 on its radially outer side, that is, an opposing region extending in the direction of the longitudinal axis 99 of the anchor bolt 20 and converging rearward, which is used to engage the expansion sleeve 10. The opposing region 27 has an axially measured width W in the radial plane. 27 In the opposite region 27, the expansion body 26 has a constant tilt angle α relative to the longitudinal axis 99 of the anchor bolt 20, at least in the radial plane. 27 .

[0050] In the illustrated embodiment, in front of the opposite region 27, the expansion body 26 has an additional region 28 extending axially in a rearward convergent direction. In this additional region 28, the expansion body 26 has, at least in the radial plane, an externally constant tilt angle α relative to the longitudinal axis 99 of the anchor bolt 20. 28 The tilt angle α in another region 28 28 The maximum outer tilt angle α of the expansion body 26 max Although the tilt angle α 28 (Not shown here) can also be greater than 30°. However, the additional region 28 is merely optional and can also be omitted, in which case the tilt angle α in the opposite region 27 is... 27 It can be the maximum outer tilt angle α of the expansion body 26 max .

[0051] At least in the radial plane, the rear side 61 is tilted at an angle β relative to the longitudinal axis 99. 61 Essentially corresponding to the tilt angle α of the expansion body 26 in the opposite region 27 relative to the longitudinal axis 99. 27 And the width w of the rear side is 61. 61 Basically corresponds to the width w of the opposite region 27 27 The rear side 61 faces forward towards the longitudinal axis 99 of the anchor bolt 20, and the opposite region 27 of the expansion body 26 faces backward towards the longitudinal axis 99 of the anchor bolt 20; that is, these two tilt angles β 61 and α 27 They open in opposite directions. Therefore, the rear side 61 is at least a mirror image of the expansion body 26 in the radial plane, particularly in the opposite region 27, and especially a reflected mirror image about a mirror axis extending parallel to the longitudinal axis 99 of the anchor bolt 20. Preferably, the following conditions apply: w 61 >0.6*d 60 / tanα maxThat is, the rear side 61 is relatively wide.

[0052] When assembling the expansion anchor, the front end of the anchor bolt 20 is pushed into the borehole in the direction of the longitudinal axis 99 of the expansion anchor. Since the sleeve stop 22 prevents displacement of the expansion sleeve 10 toward the rear end of the anchor bolt 20, the expansion sleeve 10 is also inserted into the borehole. Then, for example, by tightening the nut arranged on the load-applying structure 34 designed as external threads, the anchor bolt 20 is pulled slightly out of the borehole again. The expansion sleeve 10 remains at the rear due to its friction with the borehole wall, and the anchor bolt 20 undergoes axial displacement rearward relative to the expansion sleeve 10, during which the expansion body 26, at least axially fixed to the anchor bolt 20, penetrates deeper into the expansion sleeve 10, causing the expansion sleeve 10 to expand radially by the expansion body 26 and be compressed together with the borehole wall. This mechanism secures the expansion anchor in the base. The resulting state is... Figure 6 The diagram is shown schematically.

[0053] When the expansion anchor is used as intended, and particularly when it is installed as intended, the expansion sleeve 10 extends at the level of the rear side 61 of the first annular groove 60 onto the opposite region 27 of the expansion body 26. Because the rear side 61 of the first annular groove 60 is relatively wide and specifically forms a mirror image of the opposite region 27, the expansion sleeve is flattened at the level of the rear side 61, and the first annular protrusion 67 is pushed outwardly, which allows for… Figure 6 As seen in the image, this provides particularly good anchorage to the borehole wall.

Claims

1. An expansion anchor comprising an anchor bolt (20) and an expansion sleeve (10) surrounding the anchor bolt (20), an expansion body (26) disposed on the anchor bolt (20) for the expansion sleeve (10), the expansion body being at least partially disposed in front of the expansion sleeve (10), and the expansion sleeve (10) having a first annular groove (60) on its outer surface in the front region of the expansion sleeve (10), the first annular groove (60) having a front side surface (62) and a rear side surface (61). Its features are, The inclination angle (β) of the rear side surface (61) of the first annular groove (60) in at least one radial plane 61 The tilt angle (α) of the expansion body (26) in the opposite region (27) of the expansion body (26) 27 The expansion sleeve (10) has at least one second annular groove (70) on its outer surface in front of the first annular groove (60), and the width (w) of the second annular groove (70) is less than 8°. 70 The width of the first annular groove (60) is less than the width of the first annular groove (60). 60 The expansion sleeve (10) has at least one annular step (80) that opens in front, wherein a first annular protrusion (67) is formed between the first annular groove (60) and the second annular groove (70), and a second annular protrusion (78) is formed between the second annular groove (70) and the annular step (80), wherein the first annular protrusion (67) and the second annular protrusion (78) are aligned at their apex. The depth (d) of the first annular groove (60) 60 The depth (d) of the second annular groove (70) and the depth of the second annular groove (70) 70 )same.

2. The expansion anchor according to claim 1, Its features are, At least in the at least one radial plane, the width (w) of the opposite region (27) 27 At least the width (w) of the rear side surface (61) of the first annular groove (60) 61 They are the same size.

3. The expansion anchor according to any one of the preceding claims, Its features are, At least in the at least one radial plane, the maximum tilt angle (α) of the expansion body (26) max (greater than 10°) 4. The expansion anchor according to any one of claims 1 to 2, Its features are, In at least one radial plane, the front side (62) of the first annular groove (60) is steeper than the rear side (61) of the first annular groove (60).

5. The expansion anchor according to any one of claims 1 to 2, Its features are, In at least one radial plane, the expansion sleeve (10) has a front bevel (90) on its inner surface, and at least a portion of the first annular groove (60) is offset rearward relative to the bevel (90).

6. The expansion anchor according to any one of claims 1 to 2, Its features are, At least in the at least one radial plane, the depth (d) of the first annular groove (60) 60 At least the residual wall thickness (d) of the expansion sleeve on the first annular groove (60) 10 0.25 times that of ).

7. The expansion anchor according to any one of claims 1 to 2, Its features are, The anchor bolt (20) has a sleeve stop (22) that restricts the axial displacement of the expansion sleeve (10) away from the expansion body (26).

8. The function of the expansion anchor according to any one of the preceding claims, wherein, The expansion body (26) is inserted into the expansion sleeve (10) until the expansion sleeve (10) extends at the level of the rear side (61) of the first annular groove (60) onto the opposite region (27) of the expansion body (26).

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