Device for cutting facade anchors

Abstract

Device for cutting a facade anchor (2) to length, comprising a knife (19) insertable into a tubular end section (16) of the facade anchor (2), wherein the knife (19) is movably held on a shaft (20) of the device extending in a longitudinal direction (21), with an articulated lever (28) for advancing the knife (19) in the direction of a pipe wall (39) of the tubular end section (16), with means for rotating the shaft (20) and the knife (19) held thereon about the longitudinal direction (21), and with means for determining an axial home position of the knife (19) during cutting, wherein a linear guide (23) is provided for the knife (19), and the knife (19) is movably fixed relative to the shaft (20) via the linear guide (23),that the knife (19) is fed radially alone and / or a frontal cutting surface (35) formed during cutting to length on the facade anchor (2) is oriented perpendicular to a direction of extension (34) of the tubular end section (16), characterized in that in order to realize a variable feed movement for the knife (19) in the direction of the tube wall (39) of the end section (16), a rotatable spindle (25) with a spindle nut (26) is provided, which is guided in the shaft (20), wherein the spindle nut (26) engages with a thread of the spindle (25) and is supported on a longitudinal groove (27) of the shaft (20) extending in the longitudinal direction (21) of the shaft (20),the spindle nut (26) executes a longitudinal movement in the longitudinal direction (21) of the shaft (20) upon rotation of the spindle (25), and as a result of the longitudinal movement of the spindle nut (26), a knife holder (22) connected to the spindle nut (26) via the articulated lever (28) is displaced in a radial direction and brought into engagement with the pipe wall (39), that a fixed stop (31) is provided as a means for fixing the axial basic position of the knife (19) determined in the longitudinal direction (21), with a support surface (33) which can be applied from the outside to the facade (1).

Description

The invention relates to a device according to the preamble of claim 1.Facade anchors are fixed to this facade before performing works on a building facade in order to fix a framework, which allows the handworkers to perform the works reliably, to the facade with their aid. In particular when constructing insulating facades, these anchors remain in the facade after the facade is insulated and a last facade layer, for example a plaster layer, is applied to the insulation.The facade anchors are matched exactly to the facade thickness in the rarest cases with regard to their geometry. The facade anchors used today are usually so short that the insulating facade projects beyond the anchor and only the ring screw inserted into the facade anchor projects out of the facade. The ring screw is then plastered on when applying the outer plaster, so that the outer plaster is damaged when the screw is turned out.If adhesion of the ring screw and exterior plaster is to be prevented, the facade anchor must be designed to be long enough for the anchor to protrude from the completely plastered insulating facade. The part of the anchor protruding from the facade must be cut to length not least for visual reasons after the application of the outer plaster and the unscrewing of the ring screw. Since the anchor has to absorb considerable forces when fixing the scaffolding, in particular transverse forces acting in the facade surface, the facade anchor is of comparatively stable construction. The blank is therefore not possible without suitable auxiliary means. For example, a commercially available pipe cutter can be used for cutting the tubular end sections, as described, for example, in EP 1 243 367 B1. The pipe cutter having a plurality of round blades engages around the tubular end section from the outside. By rotating the pipe cutter and simultaneously feeding the round knives, they cut through the pipe wall. However, when using these comparatively inexpensive pipe cutters, which are widely used in particular in the installation handpiece, there is a risk that the facade will be damaged as a result of the rotation of the pipe cutter. Moreover, the facade anchor cannot be cut flush with the facade surface, since, due to the structural conditions of the pipe cutter, the facade anchor after the blank protrudes at least a few millimeters beyond the facade surface.U.S. Pat. No. 1,357,367 A discloses a pipe cutter in which two mutually opposite knives can be adjusted radially by means of a wedge kinematics and can be rotated by means of a shaft.U.S. Pat. No. 1,413,228 A also shows a pipe cutter in which three knives, which are arranged distributed in the circumferential direction, can be adjusted radially via a wedge kinematics or inclined plane.US 2 814 105 A discloses a generic device which has means for fixing it to the pipe section itself.DE 16 02 503 A1 discloses a cutting device for pipes in which a cutting blade is introduced into the pipe and the pipe wall is cut from the inside. For this purpose, the knife is pivotably held on a slender shaft. On the shaft, an actuatable kinematic mechanism is formed which allows the knife to be brought into engagement with the tube wall by pivoting it about a pivot axis oriented transversely to the tube central axis. By rotating the shaft together with the knife held thereon, the tube wall is then cut from the inside. However, due to the orientation of the knife and the pivoting movement carried out during the cutting, a cone segment-shaped cut surface is formed. A cut surface formed radially to the longitudinal direction of the tubular end section of a facade anchor cannot be realized with the device.It is therefore the object of the present invention to specify a device for cutting facade anchors to length, with which device the facade anchor installed in the facade can be shortened, preferably flush with the surface of the facade. Damage to the renovated facade surface must be reliably avoided in this case. At the same time, the device must be intuitive and easy to operate.To achieve the object, the invention has the features of claim 1.By cutting a wall of the tubular end section from the inside, damage to the newly produced facade surface is effectively prevented. The facade surface can thus be plastered from the outside onto the end section of the facade anchor. A fastening means for the scaffolding held in the facade anchor, for example a ring screw, thus does not come into contact with the exterior plaster. Contamination of the fastening means is thus effectively prevented.The core idea of the invention is to provide a device for cutting in facade anchors installed in the facade, which device enables exact trimming and reliably prevents damage to the facade. The trimming device according to the invention is therefore an aid for the facade or scaffolding builder, which can cut the facade anchors exactly and reproducibly to the dimension predetermined by the facade surface.According to a preferred embodiment of the invention, the knife is realized as a round knife. The round knife is held on the shaft in such a way that when the shaft rotates about the longitudinal axis thereof and when the wall of the end section is cut, the round knife rotates about the axis of symmetry thereof. In particular, it can be provided that the round blade is configured rotationally symmetrically with respect to an axis of symmetry thereof. Advantageously, the cutting force can be reduced by providing the round blade and the service life of the blade can be extended. At the same time, a continuous cut is formed, which improves the quality and in particular flatness of the cut surface formed at the end section.According to a further development of the invention, a fixed stop is provided as a means for adjusting the axial base position of the knife, with a support surface formed outside the anchor and bearing against the facade. Advantageously, the provision of the fixed stop eliminates the effort for setting the axial base position of the knife before cutting. Rather, the cut with the aid of the device according to the invention is always carried out at an exactly identical position defined by the position of the supporting surface of the stop. The lengthening of the facade anchor is thus particularly simple. In particular, the work can be carried out quickly and precisely by the handman even if the handman wears protective gloves which restrict his freedom of movement or motor system.For example, the shaft can be provided to be movable relative to the stop having the support surfaces. Advantageously, the relative movability between the shaft and the stop makes it possible to contact the stop on the facade surface and to avoid a relative movement between the support surface and the facade that may damage the surface of the facade. In this respect, when the tubular end section is cut, the shaft rotates with the knives while the stop rests.According to a further development of the invention, the support surface of the stop is arranged relative to the radially feedable knives in such a way that the front-side cut surface formed on the facade anchor by the blank at the end section extends in a surface plane of the facade and / or is formed set back by less than 5 mm, preferably by less than 2 mm, with respect to the surface plane of the facade. The particular advantage of the invention is that, due to the exact positioning of the support surfaces relative to a knife edge or the cut surface to be formed, an always identical closure element, designed for the previously known geometric comparisons, can be provided for closing the anchor remaining in the facade. To avoid moisture being introduced into the anchor, the closure means preferably protrudes beyond the end section on the edge side onto the facade surface. Nevertheless, a head of the closure element can be formed very thin, so that the facade continues to appear substantially planar for the observer.According to a further development of the invention, a plurality of knives is provided, wherein the plurality of knives is held on a common shank and a common cutting surface is formed on the tubular end section by means of the plurality of knives. Advantageously, by providing the knives, the cutting process can be accelerated and the wear of each individual knife can be reduced. At the same time, with a suitable orientation of the knives on the shank, the introduction of transverse forces into the shank during the blanking can be avoided. For example, two knives provided on opposite sides of the shaft or three knives fixed to the shaft offset by 120° can be provided.From the further dependent claims and the following description, further advantages, features and details of the invention result. The features mentioned in the claims and in the description can each be essential to the invention individually or in any combination. Thus, the disclosure concerning the individual aspects of the invention can always be referred to reciprocally. The drawings are intended to be illustrative only and not restrictive in character.The following are shown: FIG. 1 shows a facade anchor installed in a facade for a composite thermal insulation system with a ring screw provided herein for fixing a framework to the facade, FIG. 2 shows a device according to the invention for cutting the facade anchor according to FIG. 1 to length, FIG. 3 shows an enlarged detail of the detail X according to FIG. 2, and FIG. 4 shows an installation state of the facade anchor after it has been cut to length.FIG. 1 shows a facade anchor 2 fixed to a facade 1 and an annular screw 4 provided in a longitudinal recess 3 of the facade anchor 2. the annular screw 4 serves for fixing a skeleton, not shown, to the facade 1.The facade anchor 2 is initially fixed to a facade wall 6. For this purpose, a facade recess 7 is formed on the facade wall 6, and the facade anchor 2 is inserted into the facade recess 7 by means of an insertion section 8 formed in the manner of a dowel. By screwing the ring screw 4 into the facade anchor 2, the insertion section 8 is spread apart and the facade anchor 2 is fixed to the facade wall 6. In this case, the facade anchor 2 is supported on the facade wall 6 by means of a contact surface 9 which extends substantially parallel to a surface of the facade wall 6.Between the facade wall 6 and the contact surface 9 and in the facade cutout 7, an adhesion with an adhesive 10 is provided for further improving the fixing. Suitable adhesive 10 is, for example, a self-curing adhesive 10 or a 2-component adhesive 10.After the facade anchor 2 has been fixed to the facade wall 6 and the scaffolding has been built up, it is possible to proceed with the build-up of an insulating layer 13 and further facade layers 14, 15. By way of example, a fabric layer 14 is shown as further facade layers and an outer plaster 15 applied to the fabric layer 14 is shown as an outer facade layer 15.By providing the facade anchor 2 with support ribs 12 or other support elements in a central section 11 thereof, forces introduced via the ring screw 4, in particular transverse forces, can be supported on the facade wall 6 in the region of the contact surface 9. Due to the load-appropriate design of the facade anchor 2, in particular in the central section 11, in this respect a buckling or impermissible plastic deformation of the ring screw 4 is avoided. Damage to the facade 1 and in particular to the newly produced insulating layer 13 during removal of the ring screw 4 from the facade anchor 2 is thus prevented.In order to prevent the ring screw 4 from soiling and adhering to the outer plaster 15 during the production of the composite thermal insulation system and in particular during the formation of the outer plaster 15, the facade anchor 2 projects with a tubular end section 16 thereof out of the facade 1. The sealing body 17 ensures a seal between facade anchor 2 and facade 1.In order to shorten the tubular end section 16 after the facade 1 has been produced, the tubular end section 16 is shortened by a device 18 according to the invention for cutting the facade anchor 2 to length according to FIGS. 2 and 3. The device 18 according to the invention comprises a plurality of knives 19 which are movably mounted on a slender, elongated shaft 20 of the device 18. The shank 20 together with the knives 19 held thereon is introduced into the longitudinal recess 3 of the facade anchor 2. The knives 19 are provided so as to be linearly displaceable perpendicular to a longitudinal direction 21 of the shank 20. For this purpose, a linear guide 23 is formed on the shank 20 on the one hand and on a blade holder 22 assigned to the blades 19 on the other hand. Furthermore, the knives 19 are mounted rotatably on the knife holder 22 with respect to an axis of symmetry 24 thereof.To realize a radial feed movement of the knives 19 in the direction of a tube wall 39 of the end section 16, a spindle 25 guided in the shank 20 and having a spindle nut 26 is provided. The spindle nut 26 is firstly in engagement with a thread of the spindle 25. As a result of the longitudinal movement of the spindle nut 26, the knife holder 22 connected to the spindle nut 26 via a joint lever 28 is displaced in the radial direction and brought into engagement with the tube wall 39.For the rotation of the spindle 25, the latter has an actuating element 29. Furthermore, for the rotation of the shaft 20, a further actuating element 30, for example an actuating lever 30, is provided on the latter. The wing nut-like operating member 29 of the spindle 25 and the operating lever 30 of the shaft 20 can be rotated separately from each other.In order to achieve the most compact construction possible of the inventive trimming device 18, the shank 20 and the spindle 25 are oriented coaxially with respect to one another. The knives 19, the linear guide 23 required for fixing and actuating the knives 19 and the knife holder 22 are assigned to the shank 20 from the outside. The spindle nut 26 is provided at least in sections within the shaft 20. For this purpose, the shaft 20 is designed as a hollow shaft 20.In order to be able to cut the tubular end section 16 of the facade anchor 2 exactly and reproducibly with respect to the facade 1, the device 18 has a stop 31. The stop 31 has a plurality of support arms 32 which engage around the tubular end section 16 and support surfaces 33 which are formed on the end sides of the support arms 32. The support surfaces 33 are located in a defined position relative to the knives 19. in particular, in the illustrated working position, they extend in a common plane perpendicular to the direction of extension 34 of the facade anchor 2 in a surface plane 40 of the facade 1. Preferably, the device 18 is designed with regard to the construction and kinematics of the knives 19 such that a front-side cut surface 35 formed by the blank on the end-side tube section 16 is provided in a common plane with the support surfaces 33 and the surface plane 40 of the facade 1.According to an alternative embodiment of the invention, not shown, the knives 19 can be provided slightly set back with respect to the support surfaces 33, so that the cut surface 35 formed during the cutting is formed slightly set back with respect to the surface plane 40 of the facade 1.Identical components and component functions are identified by the same reference numerals.FIG. 4 shows the anchor 2 fixed in the facade 1 after the latter has been cut to size by means of the device 18 according to the invention. In the region of the front-side cut surface 35, the longitudinal recess 3 of the facade anchor 2 is closed by means of a screw-like closure element 36. The closure element 36 is inserted with a threaded shank 37 into the longitudinal recess 3 of the anchor 2. A head section 38 covers the tubular end section 16 and the sealing body 17 on the end face and protrudes as far as the outer plaster 15.In this respect, the device 18 according to the invention in conjunction with the facade anchor 2 permits a particularly advantageous and high-quality facade design. On the one hand, damage to the exterior plaster 15 and in particular the rumbleing of the plaster 15 when the ring screw 4 is unscrewed from the anchor 2 is reliably prevented in that the facade anchor 2 during the production of the insulating facade 1 protrudes from the same and in this respect adhesion of the exterior plaster 15 and ring screw 4 is prevented. On the other hand, the facade anchor 2 is then subsequently cut to length cleanly and precisely to the plaster surface 40 by the device 2 with the inside cutting edge 19, so that only a small opening remains. The opening can then be closed by the corresponding plug (closure element 36)).

Claims

Device for cutting a facade anchor (2) to length, comprising a knife (19) insertable into a tubular end section (16) of the facade anchor (2), wherein the knife (19) is movably held on a shaft (20) of the device extending in a longitudinal direction (21), comprising a joint lever (28) for advancing the knife (19) in the direction of a tube wall (39) of the tubular end section (16), comprising means for rotating the shaft (20) and the knife (19) held thereon about the longitudinal direction (21) and comprising means for fixing an axial base position of the knife (19) during cutting, wherein a linear guide (23) is provided for the knife (19) and the knife (19) is fixed via the linear guide (23) such that it is movable with respect to the shaft (20), the knife (19) being adjusted only radially and / or a front-side cutting surface (35) formed during cutting to length being oriented on the facade anchor (2) perpendicular to a direction of extension (34) of the tubular end section (16), characterized in that, in order to realize a variable adjusting movement for the knife (19) in the direction of the tube wall (39) of the end section (16), a rotatable spindle (25) guided in the shank (20) and having a spindle nut (26) is provided, wherein the spindle nut (26) is in engagement with a thread of the spindle (25) and is supported on a longitudinal groove (27) of the shank (20) extending in the longitudinal direction (21) of the shank (20), The spindle nut (26) performs a longitudinal movement in the longitudinal direction (21) of the shank (20) during a rotation of the spindle (25) and, as a result of the longitudinal movement of the spindle nut (26), a knife holder (22) connected to the spindle nut (26) via the articulated lever (28) is displaced in a radial direction and brought into engagement with the tube wall (39), in that a fixed stop (31) is provided as a means for fixing the axial basic position of the knife (19) determined in the longitudinal direction (21), with a support surface (33) which can be applied to the facade (1) from the outside.Device according to claim 1, characterised in that the knife (19) is designed as a round knife (19), which is held in such a way that, when the shaft (20) rotates about the longitudinal axis and a tube wall (39) of the end section (16) is cut, the round knife (19) is rotated about the axis of symmetry (24).Device according to claim 1 or 2, characterised in that the support surface (33) of the stop (31) is arranged relative to the radially feedable knives (19) in such a way that the front-side cut surface (35) formed on the facade anchor (2) by the blank extends in a surface plane (40) of the facade (1) and / or is formed set back by less than 5 mm, preferably by less than 2 mm, to the surface plane (40) of the facade (1).Device according to one of Claims 1 to 3, characterized in that a plurality of knives (19) is provided, wherein the plurality of knives (19) is held on a common shank (20) in such a way that a common cutting surface (35) can be formed on the tubular end section (16) by means of the plurality of knives (19).Device according to one of Claims 1 to 4, characterized in that the plurality of knives (19) is arranged distributed and held on the shank (20) in such a way that the shank (20) is free of transverse force when the end section (16) is cut to size.Device according to one of Claims 1 to 5, characterized in that the shaft (20) is arranged such that it can move relative to the stop (31).Device according to one of Claims 1 to 6, characterized in that the shaft (20) is designed as a hollow shaft (20), and in that at least some of the means for converting the rotational movement of the shaft (20) into the first linear movement is provided in the hollow shaft (20).Use of a device according to one of claims 1 to 7 for cutting a facade anchor (2), in particular a permanent facade anchor (2), to size for composite thermal insulation systems.

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