SK9792002A3 - Plug to be fastened to hollow and solid building materials - Google Patents

Abstract

Expansion limbs (18) are longitudinally extended from an expansion screw. A sleeve-shaped plug end (14) and a sleeve-shaped plug tip (16) are integrally connected to the leading end and rear end of the expansion limbs. A stretchable material is pierced by expansion limbs via helically arranged slots (32) on the plug tip.

Description

Technical field

The invention relates to anchors for fastening in hollow and solid building materials with the features of the preamble of claim 1. In this case, hollow building materials are meant, for example, hollow bricks or slabs behind which a cavity is located. Full building materials are for example concrete and the like.

BACKGROUND OF THE INVENTION

Such anchors are known. They are usually made of plastic and have expansive arms extending in the central region in the longitudinal direction, which are separated by notches. At the rear end, the expanding arms are connected to each other by the shell end of the armature and at the front end by the shell end of the armature. The expansion screw is pushable through the sleeve end of the anchor and screwed into the tip of the anchor. To fasten the anchor in the solid building material, the anchor is inserted into the bore in the solid building material and an expansion screw is screwed into the anchor. The expansion screw pushes the expansion arms apart; the expansion screw expands the expansion arms and thereby anchors the anchor in the borehole in solid building material.

In the hollow building material or in the plate, the anchor is pushed through the bore so that the sleeve end of the anchor is located in the hollow building material. Subsequently, the expansion screw is pushed through the end of the armature, guided between the expansion arms and screwed into the tip. anchors. By screwing the expansion screw into the anchor tip, it moves to the end of the anchor, while the expansion arms expand. Two expansion possibilities are known. The first is that by expanding the anchor tip to the end of the anchor, the expanding arms deflect outwardly and thereby engage in positive contact with the hollow building material. second

31970 / T f Cr ··· er Cr.

The possibility of the anchor tip rotating against the end of the anchor when the expansion screw is being screwed in, thus expanding the expansion arms around each other and forming a knotted formation that engages in the hollow building material.

Known anchors have the disadvantage of poor screw guidance, the expansion screw can laterally protrude through the cuts between the expansion arms when screwing in. A further disadvantage of the known anchor is its slight torsional stiffness, which, when the expansion screw is screwed on, leads to an elastic push-through of the anchor tip against the end of the anchor. When the expansion screw is screwed by hand, the elastic turning of the anchor tip relative to the end of the anchor causes the anchor tip to turn back together with the expansion screw screwed into it when the screwdriver is released for "next engagement". As a result, the expansion screw can hardly be screwed into the armature by hand.

SUMMARY OF THE INVENTION

The object of the invention is to avoid the above disadvantages.

This object is achieved according to the invention with the features of claim 1. In the anchor of the invention with the features of claim 1, the expansion arms in the circumferential direction are connected to one another by an elongate material which is interrupted by a plurality of helically grooves. For elongation, the material can be made thin and / or undulated in the circumferential direction of the anchor. In the manufacture of the plastic anchor, the stretchable material is preferably one piece with expansion arms and thus consists of the same plastic as the rest of the anchor. In this case, the stretchable material is preferably made as thin as a plastic film. By connecting the expansion arms in the circumferential direction, the anchor of the invention takes the form of a sleeve which is also closed in the circumferential direction in the region of the expansion arms. As a result, a good guiding of the expander bolt is achieved and it is avoided that the expander bolt protrudes laterally between the expander arms from the armature even when the expander bolt is laterally stressed. Another advantage of joining the expansion arms in the circumferential direction is the increased torsional rigidity of the armature. The increased stiffness in the torsion has in particular the advantage of being the tip of the anchor

31970 / T r r less co-rotates when screwing in the expansion screw, so that the expansion screw can be better screwed into the anchor tip. Furthermore, the increased stiffness has the cruel advantage that the anchor tip is less reversed when the tightening torque is released, i.e. when the screwdriver is further engaged. This makes the expansion screw easier to screw into the armature, especially when screwing in the hands. In addition, the anchor according to the invention has the advantage that the torque of the expansion screw decreases less strongly when the expansion screw is screwed in after the start of expansion in the hollow building material. With known expansible anchors, the torque decreases strongly if the expander arms start to swerve or twist around each other when fixing the anchor to the hollow building material. The increased stiffness of the anchor according to the invention due to the connection of their expanding arms in the circumferential direction makes this effect at least less. The effect of a strong decrease in the rotational torque when screwing in the expander bolt is disadvantageous, since it gives the impression that the expander bolt or anchor is torn apart by excessive overload and therefore do not have a firm seat in the hollow building material.

The torsional stiffness of the elongate material is only insignificantly reduced by the screw-shaped notches in the elongate material, but the formation of a bulge on the back of the hollow building material or board is encouraged so that both arms are almost completely and large-sized. In particular, the indentations prevent uncontrolled tearing of the elongate material in the final beading phase, which in an unfavorable case may lead to a complete breaking of the connection between the two expansion arms and, depending on the circumstances, tearing of the anchor tip.

In an embodiment of the invention, the sleeve end of the anchor has a larger diameter than the other part of the anchor. The purpose of this embodiment is to provide good anchorage in the hollow or plate-like building material, in which the anchor is retained in the bore substantially only by the sleeve end of the anchor, and the remainder of the anchor is in the cavity.

31970 / T • c r- r _{r ¾} crrr,

C r. r; · f

In an embodiment of the invention, the anchor at the outer circumference has at least two opposing and longitudinally extending anti-twist ribs which are sawtoothed over a portion of their length. The anti-torsion ribs retain the torque generated when the expansion screw is screwed in and thus prevent the anchor from co-rotating. The saw-like design of the ribs for securing against turning over a part of their length, particularly in the region of the expanding arms, results in interruptions which, on the one hand, enable the anchor to be easily driven into the bore by forming scraping edges.

In an embodiment of the invention, the sleeve-shaped anchor tip is provided with angled notches, for example in the form of a "V", wherein the projection or tip of the notches preferably points to the front or rear end of the anchor. By their angular deflection, the notches have one leg with a pitch in the direction of the thread of the expansion screw and a second leg with a reverse pitch. The pitch of the slots at the anchor tip may deviate from the pitch of the expansion screw thread, only its direction being directed in the same or vice versa. The arms of the angular slots, the pitch of which extends in the direction of the pitch of the expansion screw thread, serve to engage the speed of the expansion screw thread, causing good adaptation to different screw diameters. The angled slots cause reliable engagement of the small-diameter expansion screw without pulling the expansion screw from the anchor tip when tightening the expansion screw. At the same time, the angled slots prevent a high torque rise when the expansion screw with a high screw diameter is screwed on.

The arms of the angular notches, the pitch of which is set against the pitch of the expansion screw thread, cause axial elongation of the anchor tip, thereby varying the axial spacing of the angular notches located axially one behind the other at the anchor tip. This achieves adaptation to the different pitches of the expansion screw thread.

31970 / T

In an embodiment of the invention, the anchor has a screw channel for an expansion screw having a cross-section deviating from a circular shape inside the sleeve-shaped anchor tip. Thus, the helical channel has different transverse dimensions inside the anchor tip in different directions. This measure also serves to adapt the anchor to different diameters of the expansion screws. In another embodiment, the helical channel within the anchor tip has a flat helical channel, for example in the form of a notch. The helical channel may also have the shape of two intersecting notches inside the anchor tip.

Finally, the anchor tip may have two oppositely extending axial slits, the bottom of which is spaced from the helical channel. This embodiment achieves a further reduction of the torque for screwing in when the expansion screw is screwed into the anchor tip, since the elongation of the anchor tip is improved by the notches.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be explained in more detail with reference to the drawings, in which: FIG. 1 shows a perspective view of the anchor according to the invention, FIG. 2 is a side view of the anchor of FIG. 1; FIG. 3 shows the anchor of FIG. 1 in axial section A-A; FIG. 4 and 5 are cross-sections along planes II-II and II-II, and FIG. 6 and 7 show two examples of the use of the anchor of FIG. 1.

31970 / T •

DETAILED DESCRIPTION OF THE INVENTION

The anchor 10 according to the invention shown in FIG. 1-3 is made of plastic, it has approximately the shape of a housing. The armature 10 has a screw channel 12 for an expansion screw, not shown in FIG. 1-3, which axially extends the armature 10 and tapers conically in two places.

In the rear region, the anchor 10 has an anchor end 14 of the anchor, in the front region an anchor end 16 of the anchor, the anchor tip 16 being two opposing and extending longitudinally extending arms 18 connected in one piece to the anchor end 14. The expansion arms 18 define an expansion region 20 of the armature 10 that extends from the armature end 14 to the armature tip 16. In the circumferential direction, the expansion arms 18 are connected to each other by a stretchable material 22 which is interrupted by a plurality of helically-slotted notches 24. The stretchable material 22 consists of the same material as the rest of the armature 10, the stretchable material 22 being a one-piece part of the armature W. a thin film 22 which connects the expansion arms 18 in the circumferential direction to each other (cf. cross-section 11 of the expansion region 20 in FIG. 4). The thin film 22 has undulations in the circumferential direction. The thin film, both by its ripple and by its thin design and the elongation of the plastic of which it consists, can be elongated in the circumferential direction of the anchor 10. The screw-shaped notches 24 support the deposition of the expanding shoulders shown in FIG. tearing of thin stretchable material 22.

On the outer periphery of the armature 10, starting from the armature end 14, two opposing, anti-torsion-locking ribs 28 extending through the expansion region 20 outward to the tip of the armature 16 are provided extending to the tip of the anchor 16. of its length saw-like, with the perpendicularly standing leading edge 30 pointing in the direction of the anchor tip 16.

31970 / TR _: c

C or cr _r • r. ·. e _rr

The sleeve-shaped anchor tip 16 is provided with angularly angled slits 32 whose tip or apex is directed toward the front. The notches 32 are provided opposite each other at the anchor tip 16 at two locations, and a plurality (three) of the notches (32) are provided at the anchor tip 16 at an axial distance from each other. The angled notches 32 have arms 36, 38, the arm 36 having a pitch in the direction of the thread of the expansion screw not shown in FIG. 13, and the second arm 38 has a pitch in the opposite direction. The pitch of the arm 36 need not coincide with the pitch of the expansion screw thread, the pitch only going in the same direction.

The helical channel 12 has an approximately circular cross-section in the region of the anchor end 14, tapers in the expansion region 20 (Figure 4), and has an indentation at the anchor tip 16 (Figure 5). This allows good adaptation of the screw channel 12 to expansion screws of different diameters. For the same purpose, the two oppositely extending notches 39 in the region of the anchor tip 16, the bottom of which is spaced from the helical channel 12, serve in the axial direction.

The function of the anchor 10 according to the invention will be explained on the basis of Figures 6 and 7: Figure 6 shows the attachment of the object 40 to the sheet building material 42. The anchor 10 is inserted into a bore in the sheet building material

42. Due to the larger diameter of the armature end 14, the armature end 14 widens the bore while strengthening the building material surrounding the armature end 14. The anti-twist ribs 28 form abutment surfaces that prevent co-rotation of the armature 10 when the expansion screw 44 is screwed on.

Upon insertion of the anchor 10, the fixture 40, provided with a bore, is held on the plate building material 42, and the expander bolt 44 is pushed through the object 40 and screwed into the anchor 10. The screw thread 46 of the expander bolt 44 is cut into the anchor tip 16 and screw thread 46 engages the arms 36 of the angled notches 32 having a pitch in the same direction as the helical thread 46 of the expander screw 44. The arms 38 of the angled notches 32 having a pitch in the opposite direction allow axial extension of the anchor tip 16 so that distance

31970 / T notches 32 accommodate the pitch of the helical thread 46. In conjunction with the helical channel 12 in the form of a notch, flat at the anchor tip 16, the angled notches 32 cause the anchor tip 16 to match the diameter of the expanding screw used as well as its helical thread 46.

Upon screwing in and tightening, the expansion screw 44 pulls the anchor tip 16 in the direction of the anchor end 14, the distance between the anchor tip 16 and the anchor end 14 is reduced. In this case, the expansion arms 18 are knotted around each other so that the expansion arms 18 of the anchor 10 engage the sheet-like building material 42 by positive engagement, thereby giving a good anchorage of the anchor 10 even to the sheet-like building material 42 of lower strength such as plasterboard.

Figure 7 shows the anchoring of the article 40 on a solid building material 48 such as concrete. Here, the expansible anchor 10 is inserted in a known manner into the bore 50 in solid building material, the object 40 is inserted and the expander bolt 44 is pushed through the object 40 and screwed into the anchor 10. The expander bolt 44 pushes the expander arms 18 apart to anchor the expansible anchor 10 in the bore 50. Pushing the expanding arms apart, that is, expanding the expanding arms 18 with the thin, expanding arms 18 in the circumferential direction of the interconnecting foils 22, does not prevent them from being thin and corrugated and therefore extensible in the circumferential direction. The thin films 22, which connect the expansion arms 18 in the expansion region 20 in a sleeve-like manner, prevent the expansion screw 44 from being laterally protruding between the expansion arms 18 from the screw channel 12 when screwing.

Claims (9)

PATENT CLAIMS I An anchor for fastening in hollow and solid building materials, with expansible arms extending in the longitudinal direction, which are expandable by screwing an expander bolt into the anchor, the expansible legs at the rear end being connected to each other by the anchor end of the anchor which is expansible and at the rear end, a sleeve-shaped anchor tip into which an expanding screw is screwable, characterized in that the expanding arms (18) are connected to one another in a circumferential direction by a stretchable material (22) interrupted by a plurality of screw-shaped notches (24). Anchor according to claim 1, characterized in that the anchor end (14) has a larger diameter than the anchor (10) in the region of the expansion arms (18) and the anchor tip (16). Anchor according to claim 1, characterized in that at least two opposing and anti-twist ribs (28) extending in the sawtooth part of their length are provided on the outer periphery of the anchor (10). Anchor according to claim 1, characterized in that the anchor tip (16) has angled slits (32), wherein one leg (36) of the slope (32) has a pitch in the direction of the thread of the expansion screw (44) and the other arm (36). 38) has a climb in the opposite direction. 31970 / T • * e r · f · e · e. • · · • · «·« · «r r e r r r r r r r r r r r Anchor according to claim 1, characterized in that the helical channel (12) of the anchor (10) for the expander bolt (44) has a cross-section deviating from a circular shape inside the anchor tip (16). Anchor according to claim 1, characterized in that the helical channel (12) has a flat cross-section at least inside the anchor tip (16). Anchor according to claim 6, characterized in that the helical channel (12) is in the form of a notch. Anchor according to claim 7, characterized in that the helical channel (12) has the shape of two intersecting notches. Anchor according to claim 1, characterized in that the anchor tip (16) has two opposing notches (39) extending in the longitudinal direction of the anchor, the bottom of which extends from the helical channel (12).