Expansion anchor

Abstract

The invention proposes a design for an expansion anchor (1) having two opposite first expansion elements (3) made of plastic, with sheet metal strips (4) inserted as second expansion elements (5) in between the first elements. According to the invention, the second expansion elements (5) have a second set of teeth (12) which protrude inward or outward in a C-shape.

Description

[0001] Description

[0002] Expansion dowel

[0003] The invention relates to an expansion anchor having the features of the preamble of claim 1.

[0004] European Patent EP 3 477 126 B1 discloses a metal-plastic expansion anchor comprising a tubular, longitudinally slotted inner plastic part and a metal sleeve enclosing the inner part and slotted on one side. The expansion anchor has an expansion cone with an internal thread at the insertion end. By screwing in a screw that passes through the expansion anchor longitudinally, the cone is drawn into the inner part and the metal sleeve, thereby expanding the inner part and the metal sleeve.

[0005] The object of the invention is to propose an expansion anchor with at least one expansion element made of plastic and at least one expansion element made of metal, which provides good anchorage in an anchor hole, optionally in a solid anchor base or in an anchor base having pores or cavities. "Anchorage" here means the anchor's ability to be held against being pulled out of the anchor hole when expanded.

[0006] This problem is solved according to the invention by an expansion dowel having the features of claim 1.

[0007] The expansion anchor according to the invention extends along a longitudinal axis and comprises at least one first expansion element and at least one second expansion element, both of which extend in a longitudinal direction of the expansion anchor and are arranged around the inner longitudinal axis. "Longitudinal direction" means parallel, approximately parallel, or at an acute angle to the longitudinal axis of the expansion anchor. The longitudinal axis runs, in particular, centrally within the expansion anchor. The at least one first expansion element is made of plastic or at least comprises plastic; in particular, it is made entirely of plastic. The at least one second expansion element comprises a sheet metal strip with an L- or C-shaped cross-section. It consists, in particular, exclusively of this sheet metal strip.

[0008] To anchor the expansion anchor in an anchor hole in a base, the expansion elements can be pushed radially outwards away from the longitudinal axis by inserting an expansion pin along the longitudinal axis into the expansion anchor. This can be understood as expanding the expansion elements and the expansion anchor itself. The expansion pin is, in particular, an expansion screw or an expansion nail, and more generally, a pin-shaped element with or without a thread, suitable for expanding the expansion elements by inserting it along the longitudinal axis into the expansion anchor.

[0009] The sheet metal strip of at least one second spreading element has an L- or C-shaped cross-section when viewed in the longitudinal direction of the spreading element. The cross-section consists of a yoke and, in the case of an L-shaped cross-section, a leg attached to the yoke; in the case of a C-shaped cross-section, two legs connected by the yoke. In the case of a C-shaped cross-section, the yoke, as the central section, connects the two legs of the C-shaped cross-section, which adjoin the yoke on both longitudinal sides.

[0010] The “cross-section” of the at least one second expansion element is located in a plane perpendicular to the longitudinal direction of the at least one second expansion element or in a radial plane of the longitudinal axis of the expansion dowel.

[0011] One leg of the L- or C-shaped cross-section does not have to be uniform in the longitudinal direction. It can change its cross-section in the longitudinal direction, for example, by being interrupted by cutouts.

[0012] The yoke runs transversely to the longitudinal direction of the at least one second expansion element of the L- or C-shaped cross-section, essentially in a circumferential direction of the expansion anchor. "Circular direction" here refers specifically to a circular arc. However, the yoke can also be a straight segment or a non-circular arc around the longitudinal axis of the expansion anchor. Thus, the expression "essentially in a circumferential direction" also includes a yoke tangential to the longitudinal direction of the second expansion element, where "tangential" means a straight line perpendicular to a radial of the longitudinal axis of the expansion anchor at a radial distance from the longitudinal axis. The yoke of the L- or C-shaped cross-section of the sheet metal strip of the at least one second expansion element forms the outer surface of the second expansion element in the longitudinal direction of the expansion anchor.This outer surface can therefore be cylindrical, have a different curvature, or be flat. The inner side, which is particularly concave in the case of a curvature, faces the longitudinal axis of the expansion anchor. In the case of a flat surface, the yoke runs tangentially to a radial line to the longitudinal axis.

[0013] According to the invention, at least one leg of the L- or C-shaped cross-section of the sheet metal strip of the at least one second spreading element adjoining a longitudinal side of the yoke is directed inwards with respect to the yoke, such that the distance of the legs measured radially to the longitudinal axis is smaller than that of the yoke. Alternatively, at least one leg of the L- or C-shaped cross-section of the sheet metal strip of the at least one second spreading element adjoining a longitudinal side of the yoke is directed outwards with respect to the yoke, such that the distance of the leg measured radially to the longitudinal axis is greater than that of the yoke.

[0014] In both cases, the distance of the leg is measured at the free end of the leg, i.e., at the end opposite the yoke.

[0015] In other words, the direction in which the thigh extends differs from the circumferential direction in which the yoke extends.

[0016] "Radial" refers to the distance from the longitudinal axis, meaning that the leg, particularly the free end of the leg furthest from the yoke, has a smaller or larger radial distance from the longitudinal axis than the yoke. The leg can be curved, as can the yoke, and both the yoke and leg can have the same radius of curvature. The yoke is then the area located further out from the longitudinal axis, while the leg is the part closer to the longitudinal axis. In particular, the sheet metal stiffener has a bend at the transition between the yoke and the leg.

[0017] In particular, the leg, especially the free longitudinal edge of the leg of the L- or C-shaped cross-section of the sheet metal strip of the at least one second expanding element, touches in a radial plane to the longitudinal axis an imaginary circle concentric to the longitudinal axis of the expanding dowel, the diameter of which is smaller than a diameter of a circle concentric to the longitudinal axis of the expanding dowel in the same radial plane to the longitudinal axis, which touches an inner side of the yoke of the L- or C-shaped cross-section of the sheet metal strip of the at least one second expanding element facing the longitudinal axis.

[0018] This means that the second expanding element is designed in such a way that an expanding pin inserted into the expanding dowel initially presses against the leg before it touches the yoke, if at all.

[0019] When the expansion anchor according to the invention is expanded in an anchor hole in a solid anchor base, the leg of the L- or C-shaped cross-section of the sheet metal strip is pressed outwards, bending upwards relative to the yoke and bearing against the circumference of the expansion pin, which facilitates expansion in the anchor hole in the solid anchor base. Furthermore, the expansion anchor can expand again, at least if the sheet metal strip is made of a suitable steel, for example spring steel, if the anchor hole widens, for example as a result of a crack originating from the anchor hole, and the bent leg elastically deforms back.

[0020] In a cavity within an anchor base, the leg of the L- or C-shaped cross-section of the sheet metal strip of the at least one second expansion element is supported by the expansion pin without deformation relative to the yoke. This causes the at least one second expansion element and the sheet metal strip to expand widely, allowing, for example, the web of a perforated brick to be engaged. As a result, the expansion anchor according to the invention provides good anchorage in the cavity within the anchor base.

[0021] Preferably, the sheet metal strip is designed with a C-shaped cross-section, i.e., with two webs arranged on the longitudinal sides of the yoke, which are connected by the yoke. Particularly when both legs are directed inwards towards the longitudinal axis, this leads to a uniform radial spreading of the second spreading leg.

[0022] The dependent claims relate to advantageous embodiments and further developments of the invention specified in claim 1.

[0023] In a preferred embodiment of the invention, at least one leg of the L- or C-shaped cross-section of the sheet metal strip of the at least one second spreading element has recesses, forming second teeth. The presence of the second teeth does not require the presence of first teeth. The term "second teeth" was chosen to identify them as belonging to the at least one second spreading element.

[0024] Preferably, the sheet metal strip is C-shaped and has second teeth on both sides of the yoke. These second teeth are offset from each other on both sides of the sheet metal strip, particularly in the longitudinal direction of the at least one second expansion element or in the longitudinal direction of the expansion anchor. If the second teeth are directed inwards with respect to the yoke, the sheet metal strip is supported by the second teeth during expansion, thus bearing against the expansion pin on both sides of the yoke. Due to their elasticity, the second teeth facilitate the insertion of the expansion pin along its longitudinal axis into the expansion anchor in an anchor hole in a solid anchor base, and their elasticity also improves the subsequent expansion during the widening of the anchor hole.Furthermore, the second teeth reduce the bending stiffness of the sheet metal strip with the C-shaped cross-section of the at least one second expansion element, which allows the sheet metal strip to conform better to the anchor base when expanding in an anchor hole in a cavity-containing anchor base, thus improving the anchoring of the expansion anchor in the anchor hole.

[0025] If the teeth are directed outwards relative to the yoke, they improve anchorage by exerting a higher contact force against the wall of the anchor hole. When anchoring in a hollow brick, the teeth can also engage behind one or more webs, which improves the hold because the expansion anchor is positively locked in place.

[0026] Preferably, the inwardly directed edges of the teeth facing the longitudinal axis of the expansion anchor run obliquely inwards to the longitudinal direction of the expansion anchor, in the insertion direction of the expansion pin for expanding the expansion anchor towards the longitudinal axis of the expansion anchor. Due to the oblique course of the edges of the second teeth, when the expansion pin is inserted along the longitudinal axis into the expansion anchor, it first encounters a corner of the second teeth, which creates a tilting moment on the second teeth such that, during expansion, the second teeth pivot about imaginary axes that intersect the second teeth in radial planes to the longitudinal axis of the expansion anchor, thus improving the anchoring of the expansion anchor in the anchor hole in the anchor base. If the second teeth are directed outwards with respect to the yoke, they can also have oblique edges to the longitudinal direction of the expansion anchor in embodiments of the invention.

[0027] The at least one first spreading element preferably also has teeth on at least one of its longitudinal edges, which, to distinguish them from the second teeth of the at least one second spreading element, are referred to here as "first teeth". Preferably, the second teeth engage between the first teeth in the longitudinal direction, in particular without touching each other.

[0028] Preferably, the expansion anchor according to the invention has two first expansion elements and / or two second expansion elements. In particular, the expansion anchor according to the invention has exactly two first expansion elements and / or exactly two second expansion elements. The first expansion elements can be arranged opposite each other with respect to the longitudinal axis of the expansion anchor, and / or the second expansion elements can be arranged opposite each other with respect to the longitudinal axis of the expansion anchor. In the circumferential direction of the expansion anchor, the expansion elements are offset from each other by 90°, or the first and second expansion elements alternate in the circumferential direction.

[0029] In embodiments of the invention, the longitudinal ends of the sheet metal strip of the at least one second expansion element are mounted in the plastic of the expansion dowel, in particular in the at least one first expansion element.

[0030] With two or more secondary spreading elements, the sheet metal strips are preferably separated from each other, which facilitates automated assembly. However, versions with connected sheet metal strips are also possible, for example, those bent 180° at one front or rear end.

[0031] One embodiment of the invention provides that the expansion anchor has at least two first expansion elements that are separated from each other up to a rear end of the expansion anchor. A flange at the rear end of the expansion anchor connects the first expansion elements to each other. The flange limits the insertion depth of the expansion anchor into the anchor hole. The flange at the rear end of the expansion anchor can also be designed as an insertion funnel for the expansion pin. The expansion elements being separated from each other up to the rear end of the expansion anchor facilitate the insertion of the expansion pin between the expansion elements, thereby reducing the risk of the expansion anchor rotating with an expansion screw when being screwed into the expansion anchor.

[0032] One embodiment of the invention provides that the expansion anchor has at least two first expansion elements which are pivotally connected at their front ends. Preferably, they are connected by a hinge, for example, a film hinge. A film hinge is a thin and therefore flexible section of plastic that allows a pivoting movement of integrally adjacent, thicker, and rigid sections of plastic relative to each other. The at least two first legs and all integrally formed elements of the plastic expansion anchor are injection-molded in an open state. Subsequently, the second expansion elements are inserted, and then the first expansion elements are folded together so that they lie against each other.The rear ends of the at least two first expansion elements are connected to each other, for example by clipping them together and connecting them at the rear ends by means of a connecting device, making the expansion plug ready for use.

[0033] The features and combinations of features, embodiments, and configurations of the invention mentioned above in the description, as well as the features and combinations of features mentioned below in the figure description and / or drawn in a figure, are not only usable in the combinations specified or drawn, but also in any other combination or individually. Embodiments of the invention are possible that do not have all the features of a dependent claim. Individual features of a claim can also be replaced by other disclosed features or combinations of features. Embodiments of the invention are possible that do not have all the features of the exemplary embodiment(s), but rather any part of the characterized features of an exemplary embodiment, possibly in combination with one, several, or all features of one or more further exemplary embodiments.

[0034] The invention is explained in more detail below with reference to several exemplary embodiments shown in the drawing. The drawing shows:

[0035] Figure 1 shows a first embodiment of an expansion dowel according to the invention in a perspective view; Figure 2 shows individual parts of the expansion dowel from Figure 1;

[0036] Figure 3 shows a cross-section of the expansion dowel from Figure 1;

[0037] Figure 4 shows the cross-section according to Figure 3 with the expansion dowel spread open;

[0038] Figure 5 shows an axial section of two second expansion elements of the expansion dowel from Figure 1 during expansion;

[0039] Figure 6 shows a cross-section corresponding to Figure 3 of a second embodiment of an expansion dowel according to the invention;

[0040] Figure 7 shows a cross-section corresponding to Figure 3 of a third embodiment of an expansion anchor according to the invention;

[0041] Figure 8 shows a cross-section corresponding to Figure 3 of a fourth embodiment of an expansion anchor according to the invention; and

[0042] Figure 9 shows the second expansion elements of the expansion dowel, which are integrally formed with each other, according to the invention.

[0043] Basically, identical parts in the figures are assigned the same reference numbers.

[0044] The expansion anchor 1 according to the invention, shown in Figure 1, comprises a plastic part 2 with two elongated first expansion elements 3 and two sheet metal strips 4, which form two second expansion elements 5 of the expansion anchor 1. The plastic part 2 has the two first expansion elements 3, which are connected at their front ends 6 by a hinge 7. In the exemplary embodiment, the hinge 7 is formed by two adjacent plastic cords 8, which are integrally manufactured with the first expansion elements 3 by injection molding. The "front ends 6" here refer to the mutually facing ends 6 of the first expansion elements 3, which simultaneously form a front end 6 of the expansion anchor 1 and with which the expansion anchor 1 is inserted into an anchor hole 20 (see Figure 4) in an anchor base for anchoring.

[0045] The first expansion elements 3 each have a strip-shaped web 9 with a cylindrical outer surface, from the inside of which first teeth 10 project on both longitudinal sides of the web 9. The first teeth 10 on the two longitudinal sides of the webs 9 are offset from each other in a longitudinal direction L of the first expansion elements 3. The plastic part 2 of the expansion anchor 1 according to the invention is manufactured with the first expansion elements 3 unfolded, that is, the first expansion elements 3 are arranged in extension to each other, as shown in Figure 2, in which the individual parts of the expansion anchor 1 are depicted, namely the one-piece plastic part 2 with the two first expansion elements 3 and the two sheet metal strips 4, which form the second expansion elements 5 of the expansion anchor 1.

[0046] The two metal strips 4, which form the second metal expansion elements 5 of the expansion dowel 1 according to the invention, have an outwardly flat, strip-shaped yoke 11 that extends – in the exemplary embodiment, straight – in the longitudinal direction L of the first expansion elements 3. It forms a flat outer surface. On both longitudinal sides of the yoke 11, second teeth 12 project inwards – approximately at right angles in the first exemplary embodiment of the invention. Viewed in the longitudinal direction L, the yoke 11 and the second teeth 12 have a C-shaped cross-section, as can be seen in Figure 3. The second teeth 12 on the two longitudinal sides of the yoke 11 are offset from each other in the longitudinal direction L, just like the first teeth 10.

[0047] Each of the yokes 11 of the sheet metal strips 4, which form the second expansion elements 5, extends in the cross-section of the expansion dowel 1 or the second expansion elements 5, that is, viewed in the longitudinal direction L, in a circumferential direction of the expansion dowel 1. In the first embodiment of the expansion dowel 1 according to the invention, the yokes 11 of the sheet metal strips 4 forming the second expansion elements 5 extend straight in the cross-section of the expansion dowel 1 in a tangential direction and form part of the lateral surface and thus of the circumference of the expansion dowel 1. That is, the yokes 11 are located on a straight line that has a radial distance from the longitudinal axis A of the expansion dowel 1 and that intersects a radial of the longitudinal axis A of the expansion dowel 1 at a right angle.

[0048] Also in the cross-section of the expansion dowel 1 according to the invention, that is, viewed in the longitudinal direction L of the expansion dowel 1 and the sheet metal strips 4, the second teeth 12 are directed – in the first embodiment of the expansion dowel 1 according to the invention – at right angles inwards to the longitudinal axis A of the expansion dowel 1. The orientation of the second teeth 12 can also be understood as projecting inwards from the yoke 11 of the sheet metal strips 4. In the first embodiment, the second teeth 12 of the sheet metal strips 4 forming the second expansion elements 5 are located in two planes parallel to each other and to the longitudinal axis A of the expansion dowel 1, on both sides of the longitudinal axis A and at the same distance from the longitudinal axis A, which is less than the distance of the respective yoke 11 from the longitudinal axis A. The second teeth 12 are formed on legs 16 of the sheet metal strip 4 with a C-shaped cross-section and are components of the legs 16.For this purpose, 16 recesses 22 are arranged in the legs, through which the teeth 12 are separated from each other in the longitudinal direction L.

[0049] The sheet metal strips 4 are inserted into one of the two first, unfolded expansion elements 3 of the expansion dowel 1 according to the invention in such a way that the second teeth 12 are directed inwards and the yokes 11 are located approximately on a circumference of the expansion dowel 1 or of the first expansion elements 3.

[0050] The first two spreading elements 3 are then folded together by pivoting them 180° relative to each other at the hinge 7 at their front ends 6, such that the rear ends 13 of the first spreading elements 3, which are furthest from the front ends 6, come to lie on top of each other.

[0051] One of the first two expansion elements 3 has a perforated disc-shaped flange 14, to which the rear ends 13 of the first expansion elements 3 are connected to each other by means of detents 15 and a locking connecting device 23. The expansion anchor 1 is now ready for use.

[0052] The first expansion elements 3 of the expansion anchor 1 according to the invention are connected to each other only at their longitudinal ends and can be easily pushed outwards away from the longitudinal axis A along their remaining length, i.e., expanded. Because the first expansion elements 3 are separated from each other almost to the rear end 13 of the expansion anchor 1, an expansion screw, acting as an expansion pin 19, can be easily screwed into the expansion anchor 1 from the rear end 13 along the longitudinal axis A between the first and second expansion elements 3, 5. The low torque at the beginning of the screwing process, resulting from the first expansion elements 1 being separated from each other almost to the rear end 13, counteracts rotation of the expansion anchor 1 with the expansion screw.

[0053] Instead of an expansion screw, another pin-shaped expansion element can also be inserted into the expansion anchor 1 for expansion. For this reason, and to distinguish it from the expansion elements 3, 5, the expansion screw is also generally referred to here as an expansion pin 19.

[0054] The first spreading elements 3 are arranged opposite each other with respect to a longitudinal axis A, and the second spreading elements 5 are also arranged opposite each other with respect to the longitudinal axis A. In a circumferential direction, the first and second spreading elements 3, 5 alternate. The webs 9 of the first spreading elements 3 and the yokes 11 of the second spreading elements 5 run parallel to the longitudinal axis A, and the flange 14 is arranged in a radial plane of the longitudinal axis A.

[0055] At the front end 6 of the expansion dowel 1, the sheet metal strips 4 forming the second expansion elements 5 have angled sections 17 and transverse webs 18 (see Figure 2) that engage in complementary pockets in the front ends 6 of the first expansion elements 3. At the rear end 13 of the expansion dowel 1, the strip-shaped yokes 11 extend beyond the second teeth 12 and lie in grooves 24 that run longitudinally L in the first expansion elements 3. In this way, the sheet metal strips 4 forming the second expansion elements 5 are supported in the first expansion elements 3 at their longitudinal ends, and only there.

[0056] For anchoring in an anchor hole 20 in an anchor base, the expansion anchor 1 is inserted into the anchor hole 20 with its front end 6 leading, and then the expansion pin 19 is inserted from the rear end 13 along the longitudinal axis A between the first and second expansion elements 3, 5. For example, an expansion screw is screwed into the expansion anchor 1 from the rear end 13 between the first and second expansion elements 3, 5 as the expansion pin 19.

[0057] As shown in Figure 4, the expanding pin 19 pushes the first and second expanding elements 3, 5 outwards away from the longitudinal axis A, which can be understood as the expansion of the expanding elements 3, 5 and the expansion anchor 1. The expanding pin 19 first comes into contact with the legs 16 and pushes them outwards. The wall of the anchor hole 20 is shown as a circle in Figure 4. In a hard anchor base, for example concrete, the yokes 11 rest against the borehole wall, and the second teeth 12 of the second expanding elements 5 are pivoted outwards relative to the yokes 11 and elastically prestressed such that the C-shaped cross-sections of the second expanding elements 5 are widened. The second teeth 12 rest against the inside of the expanding pin 19, and the yokes 11 rest against the outside of the borehole wall of the anchor hole 20. If the anchor hole 20 widens, for example as a result of cracking, the second expansion elements 5 expand elastically.

[0058] In a soft anchoring base made of, for example, aerated concrete or in cavities of, for example, perforated bricks, the second expansion elements 5 are spread open, without changing their cross-section or only changing it slightly. That is, in a soft anchoring base, the C-shaped cross-section of the second expansion elements 5 is not or only slightly widened, causing the second expansion elements 5 to spread outwards considerably, as shown by the dashed lines in Figure 4.

[0059] As can be seen in Figure 5, the edges 21 of the second teeth 12 facing the longitudinal axis A of the expansion anchor 1 run obliquely at an angle α – acute in the exemplary embodiment – ​​to the longitudinal direction L or to the longitudinal axis A of the expansion anchor 1 in the insertion direction of the expansion pin 19, that is, towards the front end 6 of the expansion anchor 1 on the longitudinal axis A. As a result, when the expansion pin 19 expands, it exerts a tilting moment about tilting axes transverse to the expansion anchor 1 on the second teeth 12, which tilts the second teeth 12 like barbs or pawls. This improves the anchoring of the expansion anchor 1 in the anchor hole 20.

[0060] In the second embodiment of the invention shown in Figure 6, the second teeth 12 of the sheet metal strips 4 forming the second expanding elements 5 are bent more sharply relative to the yoke 11 than in the first embodiment. In the second embodiment, the second teeth 12 point inwards from the yoke 11 in a radial direction or almost in a radial direction to the longitudinal axis A of the expanding dowel 1. The support on the expanding pin 19 during expansion is therefore stiffer, and the second expanding elements 5 expand more and / or further.

[0061] Furthermore, the second embodiment of the expansion dowel 1 according to the invention is designed and functions in the same way as the first embodiment of the invention explained above, so that the explanations of Figures 1 to 5 are referred to in order to explain the second embodiment of the invention shown in Figure 6.

[0062] The third embodiment shown in Figure 7 differs from the first two embodiments only in that the sheet metal strip 4 is L-shaped. Here, a leg 16 is arranged on only one of the longitudinal sides of the yoke 11, on which the second teeth 12 are formed by means of recesses 22. When expanding, the second expanding element 5 is not only pressed outwards, but also pivoted about a pivot axis that runs essentially parallel to the longitudinal axis. Otherwise, the third embodiment of the expansion dowel 1 according to the invention is designed and functions in the same way as the first embodiment of the invention described above, so that the explanations of Figures 1 to 5 are referred to for an explanation of the third embodiment of the invention shown in Figure 7.

[0063] In the fourth embodiment of the expansion dowel 1 according to the invention, shown in Figure 8, the second teeth 12 of the two sheet metal strips 4 forming the second expansion elements 5, which form the legs 16, project outwards from the yoke 11 of the sheet metal strip 4 with the C-shaped cross-section. They are directed outwards and have a greater distance at their free ends from the longitudinal axis A than the respective yoke 11. In the illustrated embodiment, the second teeth 12 project outwards at approximately right angles to the yoke 11, that is, the second teeth 12 of the two sheet metal strips 4 are arranged in two planes parallel to each other and to the longitudinal axis A of the expansion dowel 1. Unlike the drawing, the second teeth 12 can also be bent outwards to a greater or lesser extent relative to the yoke 11.

[0064] Furthermore, the fourth embodiment of the expansion dowel 1 according to the invention is designed and functions in the same way as the first embodiment of the invention explained above, so that the explanations of Figures 1 to 5 are referred to in order to explain the fourth embodiment of the invention shown in Figure 8.

[0065] Figure 9 shows a variant of the second expansion elements 5 of the expansion dowel 1 according to the invention. In this case, the two sheet metal strips 4 are connected to each other at their front ends 6 by two connecting webs 25. They are stamped in one piece from a flat sheet, with the recesses 22 also being incorporated into the legs 16, thus forming the second teeth 12. The sheet metal strips are then bent into the C-shaped cross-section, and subsequently, the sheet metal strip 4 is bent at the connecting webs 25 at two angles 17 in a U-shape by 180° such that the two yokes 11 are arranged parallel at a distance and the second teeth 12 point inwards as shown in Figure 9.In the exemplary embodiment, the yokes 11 are connected at their front ends 6, but they can also be connected at their rear ends 13 (not shown) or the legs 16 or the second teeth 12 can be directed outwards, similar to Figure 8.

[0066] The integrally connected sheet metal strips 4 from Figure 9 are arranged, like the two separate sheet metal strips 4 of the other embodiments, in one of the two first expanding elements 3 of the expansion dowel 1, before the two first expanding elements 3 are folded together by 180° and clipped together at their rear ends 13 and the expansion dowel 1 is thereby made ready for use.

[0067] Reference symbol list

[0068] Expansion dowel

[0069] A Longitudinal axis

[0070] L Longitudinal direction a Angle

[0071] 1 expansion anchor

[0072] 2 plastic parts

[0073] 3 first spreading element

[0074] 4 sheet metal strips 5 second spreading element

[0075] 6 front end 7 hinge

[0076] 8 plastic cord 9 bridge

[0077] 10 first tooth

[0078] 11 yoke

[0079] 12 second tooth

[0080] 13 rear end

[0081] 14 flange

[0082] 15 rests

[0083] 16 thighs

[0084] 17 Angle

[0085] 18 Crossbar

[0086] 19 Spreader pin

[0087] 20 anchor holes

[0088] 21 Rand

[0089] 22 recess

[0090] 23 Connection device

[0091] 24 Nut

[0092] 25 Connecting bridge

Claims

Claims 1. Expansion anchor (1) extending along a longitudinal axis (A), comprising at least one first expansion element (3) made of plastic extending in a longitudinal direction (L) of the expansion anchor (1) and at least one second expansion element (5) made of metal extending in the longitudinal direction (L) of the expansion anchor (1), wherein the at least one first expansion element (3) and the at least one second expansion element (5) are movable outwards, in particular radially to the longitudinal axis (A), by inserting an expansion pin (18) inside the expansion anchor (1) between the expansion elements (3, 5), wherein the at least one second expansion element (5) has a sheet metal strip (4) extending in the longitudinal direction (L) of the expansion anchor (1) with an L- or C-shaped cross-section, characterized in thatthat a yoke (11) of the L- or C-shaped cross-section of the sheet metal strip (4) of the at least one second expansion element (5) extends substantially in a circumferential direction of the expansion dowel (1), and that at least one leg (16) of the L- or C-shaped cross-section of the sheet metal strip (4) of the second expansion element (5) is directed inwards away from the yoke (11), such that the distance of the legs (16) measured radially to the longitudinal axis (A) is smaller than that of the yoke (11), or that at least one leg (16) is directed outwards, such that the distance of the leg (16) measured radially to the longitudinal axis (A) is greater than that of the yoke (11).

2. Expansion dowel (1) according to claim 1 , characterized in that the at least one leg (16) of the L- or C-shaped cross-section of the sheet metal strip (4) of the at least one second expansion element (5) has recesses (22) whereby second teeth (12) are formed.

3. Expansion dowel (1) according to claim 2, characterized in that the sheet metal stiffener (4) is C-shaped, and second teeth (12) are formed on both sides of the yoke (11) and are in particular offset from each other.

4. Expansion dowel (1) according to claim 2 or claim 3, characterized in that inwardly directed edges (21) of the second teeth (12) extend obliquely to the longitudinal direction (L) of the expansion dowel (1) in an insertion direction of the expansion pin (19) into the expansion dowel (1).

5. Expansion dowel (1) according to one or more of the preceding claims, characterized in that the at least one first expansion element (3) has first teeth (10) on at least one of its longitudinal edges.

6. Expansion dowel (1) according to one or more of claims 2 to 4 and according to claim 5, characterized in that second teeth (12) of the at least one second expansion element (5) are arranged in the longitudinal direction (L) of the expansion dowel (1) between first teeth (10) of the at least one first expansion element (3).

7. Expansion dowel (1) according to one or more of the preceding claims, characterized in that the expansion dowel (1) has two first expansion elements (3) arranged opposite each other and / or two second expansion elements (5) arranged opposite each other.

8. Expansion dowel (1) according to one or more of the preceding claims, characterized in that the at least one second expansion element (5) is mounted at its longitudinal ends in the plastic of the expansion dowel (1).

9. Expansion dowel (1) according to one or more of the preceding claims, characterized in that the expansion dowel (1) has at least two second expansion elements (5) whose sheet metal strips (4) are separated from each other.

10. Expansion dowel (1) according to one or more of the preceding claims, characterized in that the expansion dowel (1) has at least two first expansion elements (3) extending to a flange (14) on a rear The ends (13) of the expansion dowel (1) are separated from each other, with the flange (14) connecting the first expansion elements (3) at the rear end (13).

11. Expansion dowel (1) according to one or more of the preceding claims, characterized in that the expansion dowel (1) has at least two first expansion elements (3) which are pivotally connected to each other at their front ends.

12. Expansion dowel (1) according to claim 11 , characterized in that the first expansion elements (3) are pivotally connected to each other at their front ends by a hinge (7).

13. Expansion dowel (1) according to claim 11 or claim 12, characterized in that the first expansion elements (3) have a connecting device (23) at their rear ends (13) so that the first expansion elements (3) of the expansion dowel (1) can be injection molded in an open state and can be brought into a working state by folding them together in which they are connected at the rear ends (13).

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