DE102014103717A1 - expansion anchor - Google Patents

Abstract

The invention relates to an expansion anchor (1) for anchoring in a borehole, with a shaft (2) which extends in the longitudinal direction (LR) and which has a load application means (3) at the rear in the insertion direction (E) and at the front in the insertion direction (E) Has introduction direction (E) widening spreading element (4). An expansion sleeve (5) is arranged on the shaft (2), which can be displaced in the longitudinal direction (LR) and which can be expanded with the expansion element (4). On the expansion sleeve (5) locking elements (9) for holding the expansion sleeve (5) in the borehole are arranged, which protrude radially over a base body (6) of the expansion sleeve (5) and are offset from one another in the circumferential direction (U). So that the expansion anchor (1) can also be passed through a relatively narrow through-hole in an attachment, it is proposed that the locking elements (9) be arranged in such a way that the radial extent of the expansion sleeve (5) in each radial plane (Er) is smaller than the diameter (DZ) of a cylinder (10) circumscribing the locking elements (9) in the circumferential direction (U).

Description

The invention relates to an expansion anchor with the features of the preamble of claim 1.

A generic expansion anchor is from the published patent application DE 42 19 984 A1 known. The expansion anchor has a shank with a conical expansion element with which an expansion sleeve, which is arranged displaceably on the shaft in the longitudinal direction, can be spread open. For setting the expansion sleeve in a borehole locking elements are arranged on the expansion sleeve, at the front end of the expansion sleeve as spring tongues and at the rear end as wedge-like characteristics. An expansible anchor with alternatively configured locking elements is from the published patent application DE 195 41 564 A1 known, the locking elements disclosed in the form of contiguous triangular shapes, which are arranged on expansion segments of the expansion sleeve.

A disadvantage of the known expansion anchors is that the locking elements complicate the passage of the expansion anchor through a through hole in an attachment, especially if the through hole has a relatively small diameter compared to the expansion anchor.

The object of the invention is therefore to propose an expansion anchor, which can be easily performed by a relatively narrow through hole of an attachment.

This object is achieved by an expansion anchor with the features of claim 1. The expansion anchor according to the invention is suitable for anchoring in a borehole, which was introduced in an anchoring ground, for example in concrete. The expansion anchor has a particular cylindrical, extending in the longitudinal direction shank, with a load application means, which is arranged in the direction of insertion rear of the shaft and used to attach an attachment to the anchoring ground. For this purpose, the expansion anchor is inserted through a through hole in the attachment, so that the load application means or arranged on the load application means transmission element for attachment to the attachment rests. The load application means is for example a nail head, an external thread with a nut as a transmission element or an internal thread with a screw as a transmission element, this list is not exhaustive. By "back" is not meant here that the load application means necessarily forms the rear end of the expansion anchor. The load application means may, but need not, form the rear end of the expansion anchor, but it is disposed on a rear part of the expansion anchor. In the direction of insertion in front, the shank has a spreading element widening in the direction of insertion, with which an expansion sleeve arranged displaceably on the shank in the longitudinal direction can be spread open. "Front" here also does not mean that the expansion element must form the front end of the expansion anchor. The expansion element is in particular conical, for example formed as a truncated cone. The spreading of the expansion sleeve takes place in the borehole, in which the shaft moves against the direction of insertion backwards out of the borehole while the expansion element is pulled into the sleeve. In order to prevent the expansion sleeve from moving out of the borehole with the shaft, blocking elements for holding the expansion sleeve in the borehole are arranged on the base body of the expansion sleeve. With "basic body" of the expansion sleeve is here the part of the expansion sleeve referred to, which is decisive for the outer shape of the expansion sleeve. The main body in particular has a substantially cylindrical lateral surface. In order to allow an expansion of the expansion sleeve, the expansion sleeve is partially slotted. The expansion sleeve of the expansion anchor according to the invention has slots separated from each other by Spreizsegmente, which are interconnected by a circumferentially extending collar. The blocking elements are designed, for example, as spring tongues, wedge-like or triangular shapes, teardrop-shaped curvatures, as beads or as edges, this enumeration not being conclusive. The blocking elements are radially and spatially limited over the base body and are circumferentially offset from each other, which means that a circumferential direction of the locking elements cylinder whose axis is parallel to the longitudinal axis of the shaft has a larger diameter than a cylinder, the circumscribes the main body of the expansion sleeve.

According to the invention, the blocking elements are arranged on the expansion sleeve in such a way that the radial extension of the expansion sleeve in each radial plane is smaller than the diameter of the cylinder circumscribing the blocking elements in the circumferential direction. By "radial plane" is meant any plane to which the longitudinal longitudinal axis of the shaft forms a surface normal. "Radial" also refers to the longitudinal axis and means the direction orthogonal to the longitudinal axis. By "radial extent" is meant any dimension in the radial direction within a radial plane. In other words, the diameter of a circle which circumscribes the locking elements and the base body in a radial plane is smaller than the diameter of the cylinder which circumscribes the locking elements and the base body along the length of the expansion sleeve. The center of the circle does not have to lie on the longitudinal axis of the shaft, as well as the longitudinal axis of the cylinder does not have to be aligned with the longitudinal axis of the shaft Stems coincide, but can only be parallel to this. This means that the points of maximum radial expansion of the blocking elements are not in a radial plane. The inventive design of the expansion anchor is achieved that the expansion sleeve locally, in a relation to the length of the expansion sleeve short section, a smaller diameter than when the entire length of the expansion sleeve and thus its global diameter is considered. In a well, the global diameter of the entire expansion sleeve comes into play, so the diameter of the cylinder which circumscribes the locking elements in the circumferential direction, since the expansion sleeve is completely in the borehole. If, however, the expansion anchor is passed through a through hole of an attachment whose thickness is significantly smaller than the length of the expansion sleeve, only the local diameter is relevant since it is smaller than the global diameter of the entire expansion sleeve. In particular, the through hole of the attachment can have an inner diameter which is smaller than the global diameter of the expansion sleeve, that is smaller than the diameter of the locking elements in the circumferential direction circumscribing cylinder.

The blocking elements can be arranged on the expansion sleeve such that the radial extent of a first blocking element increases in the direction of insertion, while the radial extent of a second blocking element increases counter to the direction of insertion. Alternatively, the radial extent of both expansion elements increase in the same direction, for example, opposite to the insertion direction.

In a preferred embodiment of the expansion anchor according to the invention, the blocking elements are arranged offset to one another in the longitudinal direction. That is, the locations of the maximum radial extent of two locking elements are offset from one another in the longitudinal direction. If the blocking elements are configured geometrically the same, this means in particular that the front or the rear end of two blocking elements are not located in a radial plane, as a result of which the local diameter of the expansion sleeve can be kept small.

Furthermore, it is preferred that two locking elements overlap in the longitudinal direction. "Intersecting" here does not mean that the locking elements touch, but that the two locking elements lie together in a radial section, but they are offset in the circumferential direction. Such a configuration allows a good setting of the sleeve in the borehole while good properties with respect to the passage through a through hole of an attachment.

Preferably, the locking elements are longer than their width in the circumferential direction and / or wedge-shaped. Such forms of the locking elements have proved to be particularly advantageous in terms of easy passage of the expansion anchor through a through hole in an attachment.

Preferably, at least one of the expansion segments of the expansion sleeve at least one blocking element, in particular the location of the maximum radial extent of the blocking element is arranged on at least one of. Preferably, additionally or alternatively, at least one blocking element, in particular the location of the maximum radial extent of the blocking element, is arranged on the collar. The distribution of the locking elements over the length of the expansion sleeve, ie on the collar and / or the expansion segments has the advantage that the local diameter of the expansion sleeve can be kept low.

The invention will be explained in more detail with reference to an embodiment shown in the drawing.

Show it:

1 an expansion anchor according to the invention in a side view;

2 the expansion anchor according to the invention from below;

3 a section through the expansion anchor according to the invention in the tangential plane III-III;

4 a development of the expansion sleeve of the expansion anchor according to the invention in a plan view; and

5 the settlement of the expansion sleeve in a side view.

1 shows an expansion anchor according to the invention 1 in the form of a nail anchor for anchoring in a borehole in an anchoring ground (not shown). The expansion anchor 1 has a cylindrical shaft extending along its longitudinal axis L in the longitudinal direction R _L 2 on, with a load attack 3 in the form of a nail head, the rear in the direction of insertion E on the shaft 2 is arranged. The load application 3 is designed as a circumferential shoulder in the radial direction over the part of the shaft lying in the direction of insertion E 2 over and forms the rear end of the expansion anchor 1 , With the load attack 3 For example, an attachment (not shown) may be attached to the anchorage ground. In the direction of insertion E front is on the shaft 2 a conical, expanding in the direction of insertion E, frustoconical expansion element 4 formed, with a longitudinally displaceable R _L on the shaft 2 arranged expansion sleeve 5 is spreadable. In the area of the shaft 2 in which the expansion sleeve 5 is arranged, the shaft has 3 a smaller diameter than in the direction of insertion E behind the expansion sleeve arranged part of the shaft 2 on what's in 3 can be seen.

The on the shaft 2 arranged expansion sleeve 5 has a basic body 6 with a lateral surface M on, which when attached to the shaft 2 is arranged, substantially corresponds to the lateral surface of a cylinder. The expansion sleeve 5 is made of a steel sheet. 4 shows the development of the expansion sleeve 5 in which the basic body 6 has the shape of a flat cuboid. To spread the expansion sleeve 5 to allow, is the expansion sleeve 5 with two slots 7 slotted over three quarters of its length, leaving the expansion sleeve 5 three in the radial direction r pivotable expansion segments 8th has, at its rear ends by a covenant 14 connected to each other. The slots 7 ends in round openings 12 which causes joints 13 are formed to the the spreading segments 8th can be rotated for spreading. For spreading the expansion sleeve 5 becomes the shaft 2 of the expansion anchor 1 opposite to the direction of insertion E relative to the expansion sleeve 5 moves, leaving the spreader 4 in the slotted part of the expansion sleeve 5 is moved into it. To the expansion sleeve 5 in a hole, not shown, so that they do not spread with the shaft when spreading 2 is moved out of the borehole, are on the expansion sleeve 5 three blocking elements 9 arranged at the on the shaft 2 arranged expansion sleeve 5 in the radial direction over the cylindrical base body 6 the expansion sleeve 5 survive. The blocking elements 9 are at the expansion anchor 1 in the circumferential direction U offset from each other with a distance a _U arranged.

The blocking elements 9 are all wedge-shaped and geometrically configured the same, with their radial extent counter to the direction of insertion E to a place 15 the maximum radial extent increases. The length Z of each locking element 9 is greater than its width Y and the blocking elements 9 are so on the body 6 the at the expansion anchor 1 attached expansion sleeve 5 arranged that the radial extent of the expansion sleeve 5 in each radial plane E _{r is} smaller than the diameter D ₂ of the locking elements 9 in the circumferential direction U circumscribing cylinder 10 , This means that the diameter D _{K of} a circle 11 in a radial plane E _r the blocking elements 9 locally smaller than the diameter D _{2 of} the cylinder 10 that the locking elements 9 globally over the length L _{S of} the expansion sleeve 5 rewrites. In 2 is the blocking elements 9 in the circumferential direction U circumscribing cylinder 10 drawn in and visible as a perimeter whose central axis M _Z lies on the longitudinal axis L. 3 on the other hand shows a section through the expansion anchor 1 in the radial plane E _r . The diameter D _K of the lying in the radial plane E _r circle 11 is smaller than the diameter D _{2 of} the cylinder 10 , where the midpoint M _{K of} the circle 11 not on the longitudinal axis L of the shaft 2 lies. The blocking elements 9 are arranged offset in the longitudinal direction L _R each other. This means the places 15 the maximum radial extent of the locking elements 9 do not lie in the radial plane E _r . The rear in the direction of insertion E and front ends of the locking elements 9 are spaced apart in the longitudinal direction L _R. However, each two locking elements overlap 9 in the longitudinal direction L _R , ie in each case two locking elements 9 lie in the radial plane E _r , wherein they are offset in the circumferential direction U to each other. The blocking elements 9 are arranged offset in the longitudinal direction L _R that the rear in the direction of insertion E blocking element 9 at the federal government 14 and the front locking element 9 on a spreading segment 8th is arranged.

Due to the inventive design of the expansion sleeve 5 of the expansion anchor 1 can the expansion sleeve 5 also by a relatively narrow through hole of an attachment whose diameter is smaller than the diameter of the cylinder 10 can be perform without the function of the blocking elements 9 of the expansion anchor 1 is impaired.

LIST OF REFERENCE NUMBERS

1

expansion anchor

2

shaft

3

Load application means

4

spreader

5

expansion sleeve

6

body

7

slot

8th

spacer segment

9

blocking element

10

the blocking elements 9 circumscribing cylinder

11

the blocking elements 9 in a radial plane E _r circumscribing circle

12

opening

13

joint

14

Federation

15

Location of the maximum radial extension of a barrier element 9

a _U

Distance between the locking elements 9

D _K

Diameter of the circle 11

D ₂

Diameter of the cylinder 10

e

of introduction

E _r

radial plane

L

longitudinal axis

L _S

Length of the expansion sleeve 5

M

lateral surface

M _K

Center of the circle 11

M _Z

Central axis of the cylinder 10

r

radial direction

R _L

longitudinal direction

U

circumferentially

Y

Width of a barrier element 9

Z

Length of a barrier element 9

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4219984 A1 [0002]
• DE 19541564 A1 [0002]

Claims (7)

Expansion anchor ( 1 ) for anchoring in a borehole, with a shank (L _R ) extending in the longitudinal direction ( 2 ), which in the insertion direction (E) behind a load application ( 3 ) and in the introduction direction (E) at the front in the insertion direction (E) expanding expansion element ( 4 ), with which in the longitudinal direction (R _L ) displaceable on the shaft ( 2 ) arranged expansion sleeve ( 5 ) is spreadable, wherein the expansion sleeve ( 5 ) through slots ( 7 ) separate spreading segments ( 8th ) which extends through a circumferentially extending (U) collar ( 14 ) are connected to each other, wherein at the base body ( 6 ) of the expansion sleeve ( 5 ) Blocking elements ( 9 ) for holding the expansion sleeve ( 5 ) are arranged in the borehole, which radially over the base body ( 6 ) and in the circumferential direction (U) are arranged offset from one another, characterized in that the blocking elements ( 9 ) are arranged such that the radial extent of the expansion sleeve ( 5 ) in each radial plane (E _r ) is smaller than the diameter (D ₂ ) of one of the blocking elements ( 9 ) in the circumferential direction (U) circumscribing cylinder ( 10 ). Expansion anchor according to claim 1, characterized in that the blocking elements ( 9 ) are offset in the longitudinal direction (R _L ) to each other. Expansion anchor according to claim 1 or 2, characterized in that two locking elements ( 9 ) in the longitudinal direction (R _L ) overlap. Expansion anchor according to one of claims 1 to 3, characterized in that the length (Z) of the locking elements ( 9 ) is greater than its width (Y) in the circumferential direction (U). Expansion anchor according to one of claims 1 to 4, characterized in that the locking elements ( 9 ) are wedge-shaped. Expansion anchor according to one of claims 1 to 5, characterized in that on at least one of the expansion segments ( 8th ) at least one blocking element ( 9 ) is arranged. Expansion anchor according to one of claims 1 to 6, characterized in that on the collar ( 14 ) at least one blocking element ( 9 ) is arranged.

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