DE202012001547U1 - Fixing anchor and fixing system with fixing anchor - Google Patents

Abstract

Fastening anchor (10), which can be positively fixed in a recess (A) of a component (T) to be fastened, such as a plate for wall cladding, the fastening anchor (10) having an expansion cylinder (1) which is hollow-cylindrical in shape and provided in a Direction of insertion (e) into the recess (A) has rear end region (2.1) which is longitudinally segmented into individual expansion elements (4) which can be expanded radially to the direction of insertion (e), characterized in that the expansion elements (4) each have a direction of insertion ( 12) with a cutting edge (13) arranged radially on the outside for the form-fitting cutting of the cutting projection (12) radially outwards into a wall (W) of the component (T) to be fastened which delimits the recess (A), with the expansion elements (4) spreading radially has outside in a mounting position.

Description

The invention relates to a fastening anchor which can be fixed in a form-fitting manner in a recess of a component to be fastened, such as a panel for wall cladding, wherein the fastening anchor has a hollow-cylinder-like expansion dowel in the basic form with a rear end region in an intended insertion direction into the recess radially spreadable to the insertion direction spreading elements is longitudinally segmented. The invention further relates to a fastening system with the fastening anchor.

Generic fastening anchors can be clamped, for example dowel-like in the recess, which can lead to an unfavorable radial pressure load on the wall of the plate and / or in particular for softer plates to a loosening of the fastening anchor in the recess.

In the EP 0 336 183 A2 and the DE 93 06 937 U In each case, a fastening anchor designed as an undercut anchor is described which, in order to avoid an unfavorable radial pressure load, positively engages only in an undercut of an undercut recess. This is more suitable for plates made of a stronger material, such as natural stone or concrete. For slabs with lower strength, the undercut anchor can be loosened at even lower loads.

The object of the invention is to provide a generic fastening anchor which can be mounted while reducing the radial pressure load on the wall of the recess and yet under a firm seat in the recess.

The stated object is achieved by the features of claim 1. Advantageous developments are described in the subclaims. The stated object is already achieved in that the spreading each radially to the insertion direction radially outwardly extending cutting projection with a radially outer cutting edge for positive cutting of the cutting projection radially outwardly into a recess bounding wall of the component to be fastened under spreading of the spreading radially has outwardly into a mounting position inside.

The cutting projection is designed to cut radially outwards into the wall in a cutting direction, or, in particular, to dig in a wall of soft material. With the cutting of the cutting projection in the wall of the recess, an undercut is produced to the recess in which the cutting projection in the fastening position rests positively. Since the cutting projection generates the undercut, the undercut is identical in shape with the cutting edge projection, so that a particularly tight fit of the cutting edge projection and thus of the fastening anchor is ensured in the recess. It is obvious that such a fastening anchor for soft to medium-hard material is suitable so that the cutting edge projection can easily cut into the wall and thus dig into the wall.

The spreading elements preferably extend in the fastening position in the longitudinal direction of the fastening anchor.

The cutting projections can thus protrude radially outward in the fastening position. The rear end region with the spreading elements can thus have a diameter greater than that of the recess in the fastening position in the amount of the cutting edge projections. To reduce the diameter, the expansion elements can be bent into a position of insertion radially inwards before insertion into the recess, in which they can be inserted into the recess. Here, the bending radially inwardly purely elastic, but preferably done plastically. It can thus be arranged bent radially inward in the provision position for insertion of the fastening anchor into the recess in radial adjustment to the same. The expansion anchor can be preferably limited stop used up to a certain height in the direction of insertion into the recess. Upon reaching this height, the spreading can be bent by introducing a bending moment preferably end of the spreading from the ready position into the mounting position. In this case, the cutting projections can cut radially into the wall or dig in to form the undercut. In order to fix the fastening anchor in the recess, the spreading elements in the recess can be arranged so spread radially outwards from the provisioning position into the fastening position that the spreading elements are arranged at least approximately parallel to the longitudinal direction of the fastening anchor.

In terms of manufacturing technology, the expansion elements can extend parallel to the longitudinal axis after production. In terms of force mechanics, the cutting projection can be arranged in the insertion direction at the rear on the associated expansion element.

The cutting projection can be designed to converge outwardly over its radial extension to the cutting edge. Thus, the cutting edge projection has no shape jump on, which would counteract a slight penetration of the cutting edge projection into the wall of the recess.

Preferably, the cutting projection is formed prismatic to the cutting edge converging. The cutting projection can have a front edge in the insertion direction and a rear edge in the insertion direction. These can converge radially outward to form the cutting edge. Here, the front edge may be arranged inclined in a first cutting angle to the radial direction. This first cutting angle may have an amount in the range of 5 ° to 30 °, preferably 8 ° to 20 °, or more preferably 10 ° to 15 °. An ideal first cutting angle depends, among other things, on the material of the wall.

Depending on the size of the first cutting angle may also be an excavation work that must be applied to tear the fastening anchor out of the recess with at least partial destruction of the recess. The spreading of the spreading radially inward and / or radially outward, as already described, can be done under bending of the spreading. With the introduction of a required bending moment in the direction of insertion in the back of the spreading is the foot of the spreading, d. H. in the insertion direction forward, generates a maximum bending moment in the expansion elements. This can be done with the introduction of the bending moment at the foot of the spreading a maximum bending of the same in the radial direction. Thus, the radial spread of the spreading with respect to the cutting edge projections can be interpreted as pivoting on a circular path. In order for the cutting projection to be able to penetrate with this pivoting radially outwards more easily into the wall, the rear flank is inclined in a second cutting angle to the radial direction. The second cutting angle may have an amount in a range of ≥ 0 ° to ≦ 10 °, or preferably 1 ° to ≦ 7 °. An ideal second cutting angle can depend, for example, on the length of the spreading elements as a function of the diameter of the recess and / or on the material of the wall of the recess. An ideal angle range of ≥ 10 ° to ≤ 15 ° may occur.

The greater a radial extension of the cutting projection, the deeper the cutting projection can engage in the wall of the recess. A value of the optimal radial extension of the cutting edge projection may depend inter alia on the material of the wall of the recess, that is, the softer this material is and / or the easier an incision can be made in the same by means of the cutting edge projection, the higher the radial extent of the Cutting edge are selected, but advantageously without incising a higher mechanical stress on the recess outside the range of engagement of the cutting edge projection into the wall to produce. Constructively, a maximum extension can then be limited by the diameter of the recess when the expansion elements, as described above, are bent radially inward for insertion into the recess because of the protruding cutting edge projections. If, for example, three or more expansion elements are provided here, then they can abut one another with their bending radially inwards in the insertion direction in the center. In this case, the maximum radial extent of the expansion elements in height of the cutting edge projections equal to the radius of the recess, be less than the radius of the recess in plastic bending of the expansion elements corresponding to an elastic bending part in the plastic bending.

In particular, with larger diameters of the recess, it may be cheaper because of the structurally related longer cutting edge of the cutting edge projection with respect to the mechanical load on the wall when cutting the cutting edge projection in the same, to choose a smaller radial extent of the cutting edge projection. The radial extent of the cutting edge projection and the inner radius of the rear end portion of the fixing anchor can form a radial extension / inner radius ratio of 1/6 to 1/1, preferably 1/5 to 2/3, and ideally 1/4 to 1/2 is.

The rear end region of the expansion anchor can be segmented by means of two preferably perpendicular to each other central longitudinal cuts in four expansion elements. The spreading elements can thus be arranged axially symmetrical to the longitudinal axis of the expansion anchor. As a result, the expansion dowel as a precursor without the central longitudinal incisions in the rear end region have the cutting projection as a circumferential projection, which is segmented with segmentation of the expansion elements.

In a preferred embodiment, the fastening anchor can have a bolt element for spreading the spreading elements out of the ready position into the fastening position and for the radial abutment of the spreading elements in the fastening position. The hollow cylinder-like expansion dowel may have a central opening formed as a passage opening. The bolt element can be introduced in the insertion direction into this opening, preferably stop-limited. Reaches the bolt in the insertion direction which is in the ready position Spreading, so he can attack with further introduction in the insertion direction end radially inward under the introduction of a moment of force radially outward on the spreading, which are thereby spread radially outward.

Preferably, it is provided that the bolt element is stop limit so far inserted in the insertion direction in the expansion dowel until it is arranged with its end face flush with the end faces of the expansion elements. By spreading the spreading elements, the associated cutting projections can cut into the wall of the recess. With the cutting at the same time an undercut is produced in the recess, which precludes a removal of the fastening anchor against insertion direction.

For easier spreading of the spreading elements, they can each have a predetermined bending point in the direction of insertion in front of the cutting projection. This predetermined bending point as a weak point in the bending strength curve of the spreading over the length thereof may be formed so that the bending of the expansion elements during their spreading takes place at least almost exclusively at the predetermined bending point. Thus, the spreading can be practically pivoted to the predetermined bending point and maintain their stretched shape over this. This can apply to a radial spread inwards and outwards.

Preferably, the predetermined bending point is provided at the foot end of the spreading elements. This means that the predetermined bending point can be arranged directly in the region of the spreading elements to which the spreading elements are connected to the remaining expansion dowel. This is also a force-mechanically favorable point, since, at endstirnseitig initiated radial force, here a maximum bending moment acts.

• – Einsetzen des Spreizdübel des Befestigungsankers in die Ausnehmung bis zu einer bestimmten Höhe,
• – Spreizen der Spreizelemente beispielsweise mittels eines in die Öffnung des Spreizdübels eingeführten Bolzenelementes unter Einschneiden oder Eingraben der Schneidenvorsprünge in die Wandung der Ausnehmung, bis sich die Spreizelemente in der Befestigungsposition befinden.

The fastening anchor can form a fastening system with the recess, wherein the fastening anchor generates an undercut in the recess by cutting its cutting projections. The fastening anchor can thus be determined with the following steps in the recess:

• Inserting the expansion anchor of the fastening anchor into the recess up to a certain height,
• - Spreading of the spreading, for example by means of an inserted into the opening of the expansion anchor bolt element while cutting or digging the cutting edge projections in the wall of the recess until the expansion elements are in the mounting position.

In the attachment position, the spreading elements preferably extend parallel to the wall of the recess, so that only the Schneidvarsprünge force effective at the bez. engage in the wall of the recess.

The expansion anchor can have a front end region in the insertion direction. It can protrude in the mounting position with the rear end portion on the recess. For example, the expansion dowel can be designed as a collar dowel with a collar, wherein the collar in the mounting position, the recess can strike radially across the front of the component in the insertion direction. The front end region of the expansion anchor and / or the front end section of the bolt element can each have connecting elements for connection to fastening structures and / or for tool engagement.

The bolt element can be designed as a threaded bolt with a first external thread provided in a rear end section in the insertion direction. Accordingly, the expansion anchor can preferably have at least in its rear end region an internal thread, which is designed for thread engagement with the first external thread of the bolt element. The threaded engagement of bolt element and expansion dowel reduces a possible load on the recess.

As an alternative to the bolt element, the fastening system can additionally be designed such that the recess is provided on the sole side with a sole cone. The expansion elements may have a common end adapted to the sole cone preformed conical return to the end-side sliding of the expansion elements on the sole cone under radial spread thereof. Thus, the spreading can be spread on the sole cone by sliding off with their conical return with insertion into the recess.

The present invention will be described below with reference to several embodiments of the fastening anchor or mounting system with fastening anchor shown in a drawing. In the drawing show:

1 FIG. 2: a side view with partial longitudinal section of a first embodiment of an expansion anchor in a fastening position for a fastening anchor, FIG.

2 a side view of a bolt element for insertion into the expansible plug,

3 : a section of the expansion anchor according to the section III in 1 .

4a : A side view with partial longitudinal section of the first embodiment of the expansion anchor according to 1 but in a provision position in a recess in a component to be fastened,

4b a side view with partial longitudinal section of a second embodiment of the expansion anchor in the provision position in the recess and

5a to 5c in each case a side view with partial longitudinal section of a fastening system with fastening anchor and recess in the component to be fastened, to illustrate a determination of the fastening anchor in three steps.

In 1 is a side view with partial longitudinal section a first embodiment of a expansion anchor 1 shown. This is used in a recess formed here as a blind hole A of a component to be fastened B in an insertion direction e and fixed there. The expansion dowel 1 has a rear end region in the insertion direction e 2.1 on, here by means of two mutually perpendicular central longitudinal incisions 3 in four spreading elements 4 is segmented. The expansion dowel 1 has a substantially hollow cylindrical shape with a central opening formed as a through hole 5 on.

In 2 is a side view of one here as a bolt 7 trained screw 6 shown having a rear end portion in the insertion direction e 8.1 with a first external thread 9.1 and a front end portion in the insertion direction e 8.2 with a second external thread 9.2 having. expansion anchor 1 and bolts 7 form a fastening anchor in the figures shown here 10 who, as in 5c shown, together with the recess A forms a fastening system B. For this purpose, the bolt 7 in the insertion direction e in the opening 5 of the expansion anchor 1 used and engages with its first external thread 9.1 in one in the opening 5 of the expansion anchor 1 provided internal thread 11 one ( 5c ).

The spreading elements 4 have in the direction of insertion e behind each a cutting edge projection 12 on, extending radially outward to form a radially outer cutting edge 13 extends by an amount a. This amount a forms with half the diameter d of the rear end portion 2.1 without cutting edge 12 in the embodiments of the expansion anchor shown here 1 a ratio 2a / d of about 1: 3 ( 1 ).

1 gives the expansion dowel 1 in the form again, in which it is made with still unexpanded spreading elements and in which it is after prior radial spread inward and radial spread outwards in a mounting position in the recess A ( 5b ). Here, the spreading elements extend 4 in longitudinal axis 1 of the expansion anchor 1 , To the protruding cutting edge projections 12 be used in the insertion direction e in the recess A, the spreading are 4 bent radially inwardly, as purely schematically in the 4a and 4b is shown. Inserted into the recess A, in the bolt 6 in the opening 5 introduced, with its first external thread 9.1 in the internal thread 11 of the expansion anchor 1 engages and with further screwing in the expansion dowel 1 the spreading elements 4 bends in the direction of insertion e forward radially outward. These intersect in turn by means of their cutting projections 12 in which the recess A bounding wall W to form an undercut H in the wall W, by means of which the expansion dowel 1 and thus the fastening anchor 10 axially fixed in the recess A ( 5c ).

The cutting edge projection 12 has a front edge in the insertion direction e 14.1 and a trailing edge in the insertion direction e 14.2 on the radially outward to the cutting edge 13 converge. The front flank 14.1 forms with a radial direction r a first angle β1, which is exemplary here about 20 °. Accordingly, the rear edge closes 14.2 with the radial direction r a second angle β2, which is exemplary here about 5 °. The first angle .beta.1 is designed for a relatively soft wall W, in order to maximize excavation work when breaking out the fastening anchor 10 to cause from the recess A and thus the most secure fit of the mounting anchor 10 to effect in the recess A. The second angle β2 serves primarily to the cutting edge 14 with the spreading of the spreading elements 4 , the pivoting of the spreading elements 4 at their respective base 15 equals to penetrate as possible friction in the wall W.

For easier spreading or pivoting of the spreading 4 is the foot side of the spreading elements 4 in each case a predetermined bending point 16 intended. The predetermined bending point 16 is here designed so that the bend and thus virtually a pivoting of the expansion elements 4 at the bottom 15 the same takes place. This has the advantage that the shape of the spreading elements stretched from the production point 4 after their spread radially inward into the ready position and their spread radially outward in their mounting position is at least almost maintained. The predetermined bending point 16 is here as a cross-sectional taper in the form of a groove 17 introduced with a round cross-section. This groove 17 is from the manufacturing process of the expansion anchor 1 before introducing the central longitudinal cuts 3 in the rear end area 2.1 as a circumferential ring groove 17 brought in.

The insertion of the expansion anchor 1 in the recess A and the bolt 7 in the opening 5 of the expansion anchor 1 each in the insertion direction e is how 5 clearly removable, each stop limited by the expansion dowel 1 in the insertion direction e at the edge of the recess A on the component T and the bolt 7 at the edge of the opening 5 in the insertion direction e front of the expansion dowel 1 attacks.

The expansion dowel 1 points in a direction of insertion e front end 2.2 as a stop a collar 18 on, in the attachment position, the recess A in the insertion direction e overlaps front. Furthermore, what is not specifically shown here, the collar 18 flattened laterally on two radially opposite areas outside to attack on a tool, not shown here. Thus, the expansion dowel 1 after its insertion into the recess A ( 4a and b) rotationally held in the recess A to the bolt 7 in the opening 5 of the expansion anchor 1 to screw in trouble-free.

The bolt 7 points in its front end portion 8.2 a tool opening 19 , here for here an Allen key, not shown here, on, over which the bolt 7 in the opening 5 of the expansion anchor 1 can be screwed.

About the second external thread 9.2 of the bolt 7 a connection option for fastening structures not shown here is provided.

LIST OF REFERENCE NUMBERS

1

expansion anchor

2.1

rear end area

2.2

front end area

3

Central longitudinal incision

4

spreader

5

opening

6

cutting edge

7

bolts

8.1

rear end section

8.2

front end section

9.1

first external thread

9.2

second external thread

10

fastening anchor

11

inner thread

12

cutting edge

13

cutting edge

14.1

front flank

14.2

behind flank

15

nadir

16

Predetermined bending point

17

round slot

18

collar

19

mold opening

a

amount

e

insertion

l

longitudinal axis

r

radial direction

A

recess

B

fastening system

H

undercut

T

component

W

wall

β1

first angle

β2

second angle

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

• EP 0336183 A2 [0003]
• DE 9306937 [0003]

Claims (15)

Fixing anchor ( 10 ), which in a recess (A) of a component to be fastened (T), such as a plate for wall cladding, can be fixed in a form-fitting manner, wherein the fastening anchor ( 10 ) in the basic form hollow cylinder-like expansion dowel ( 1 ) with a rear end region (A) in the recess (A) in an intended insertion direction (e) 2.1 ) which in individual radially to the insertion direction (e) spreadable spreading elements ( 4 ) is longitudinally segmented, characterized in that the spreading elements ( 4 ) each one to the insertion direction (e) radially outwardly extending cutting edge projection ( 12 ) with a radially outer cutting edge ( 13 ) for the positive cutting of the cutting edge projection ( 12 ) radially outwardly into a recess (A) limiting wall (W) of the component to be fastened (T) with spreading of the spreading elements ( 4 ) radially outward into a mounting position. Fixing anchor ( 10 ) according to claim 1, characterized in that the cutting projection ( 12 ) over its radial extent (a) continuous to the cutting edge ( 13 ) converges. Fixing anchor ( 10 ) according to claim 1 or 2, characterized in that the cutting projection ( 12 ) prismatic to the cutting edge ( 13 ) converges. Fixing anchor ( 10 ) according to one of claims 1 to 3, characterized in that the cutting projection ( 12 ) in the insertion direction (e) front edge ( 14.1 ) and in the insertion direction (e) rear edge ( 14.2 ), which radially outward to form the cutting edge ( 13 ) converge, the leading edge ( 19.1 ) is inclined in a first cutting angle (β1) to the radial direction (r). Fixing anchor ( 10 ) according to claim 4, characterized in that the first cutting angle (β1) has an amount in the range of 5 ° to 30 °, preferably 8 ° to 20 ° or 10 ° to 15 °. Fixing anchor ( 10 ) according to claim 4 or 5, characterized in that the trailing edge ( 14.2 ) is inclined at a second cutting angle (β2) to the radial direction (r). Fixing anchor ( 10 ) according to claim 6, characterized in that the second cutting angle (β2) has an amount in the range of 0 ° to 10 °, preferably 1 ° to 7 ° or ideally 2 ° to 4 °. Fixing anchor ( 10 ) according to one of claims 1 to 7, characterized in that the cutting projection ( 12 ) a radial extension and the rear end region ( 2.1 ) of the expansion anchor ( 1 ) have a radius forming a radial extent / radius ratio of 1/6 to 3/4, preferably 1/5 to 2/3 and ideally 1/4 to 1/2. Fixing anchor ( 10 ) according to one of claims 1 to 8, characterized in that the cutting projection ( 12 ) in the insertion direction (e) at the rear of the respective associated expansion element ( 4 ) is arranged. Fixing anchor ( 10 ) according to one of claims 1 to 9, characterized in that the spreading elements ( 4 ) in a ready position for insertion of the expansion anchor ( 1 ) in the recess (A) in radial adaptation to the same radially inwardly bent to each other and fixing the expansion anchor ( 1 ) in the recess (A) from the ready position in a mounting position are radially spread outwardly so that the spreading elements ( 4 ) at least approximately parallel to the longitudinal axis ( 1 ) of the expansion anchor ( 1 ) are arranged. Fixing anchor ( 10 ) according to one of claims 1 to 10, characterized in that the rear end region ( 2.1 ) by means of two mutually perpendicular central longitudinal cuts ( 3 ) in four spreading elements ( 4 ) is segmented. Fixing anchor ( 10 ) according to one of claims 1 to 11, characterized in that it comprises a bolt element ( 7 ), for spreading the spreading elements ( 4 ) from a ready position in which the spreading elements ( 4 ) are bent radially inwardly to the radial adaptation to the recess (A) of the component to be fastened (T), into a fastening position, in the cutting projections ( 12 ) radially outwardly into the wall (W) incisive engage, and for the radial abutment of the expansion elements ( 4 ) in the attachment position in an opening formed as a passage opening ( 5 ) of the hollow cylinder-like expansion anchor ( 1 ) is insertable. Fixing anchor ( 10 ) according to one of claims 1 to 11, characterized in that the spreading elements ( 4 ) in the insertion direction (e) before the cutting edge projection ( 12 ) each have a predetermined bending point ( 16 ), on which the spreading elements ( 4 ) for engagement of the cutting edge projections ( 12 ) are radially bendable in the wall (W). Fixing system with a recess (A) of a component (T) to be fastened and a fixing anchor which can be fixed in a form-fitting manner in the recess (A) ( 10 ) according to one of claims 1 to 11, wherein the fastening anchor ( 10 ) in the basic form hollow cylinder-like expansion dowel ( 1 ) with an insertion direction (e) provided in the recess (A) rear end region ( 2.1 ) which in individual radially to the insertion direction (e) spreadable spreading elements ( 4 ) is longitudinally segmented, and the spreading elements ( 4 ) each one to the insertion direction (e) radially outwardly extending cutting edge projection ( 12 ) with a radially outer cutting edge ( 13 ) for the positive cutting of the cutting edge projection ( 12 ) radially outwardly into a recess (A) defining wall (W) of the component to be fastened (T) in a mounting position inside. 15. Fastening system according to claim 12, characterized in that the spreading elements ( 4 ) in the mounting position except for the cutting edge projections ( 12 ) spaced from the inner wall of the recess (A) are arranged. Fastening system according to claim 13 or 14, characterized in that the recess (A) is provided on the sole side with a sole cone and the spreading elements ( 4 ) at the end common to the sole cone adapted preformed conical return to the end slipping of the spreading ( 4 ) on the sole cone with radial spreading thereof.

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