TITLE
Anchoring device
FIELD OF THE INVENTION
The present invention relates to an anchoring device for a facing at a building framework, which device comprises a sheet metal wall attachment which is provided with a longitudinal stiffening means and which m the position of use forms a substantially horizontal connection between the framework of the building and the outer facing. Also, the invention relates to a method for mounting the device .
BACKGROUND OF THE INVENTION
Anchoring devices according to the above are used for anchoring an outer facing wall, e.g. a cavity wall of bricks, calcareous sandstone or concrete blocks and/or an insulation to an inner supporting framework, so that the cavity wall or the insulation will not fall down because of wind pressure or wind suction. Because the cavity wall, which among other constitutes a climate screening, is positioned outside the insulated part of the outside wall, the cavity wall is exposed to considerably larger movements induced by temperature and moisture, than the framework lying behind. Behind the cavity wall there is an air gap of 20-40 mm and usually there is a mineral wool insulation between the framework and the back side of the cavity wall . Because of the variations m temperature, the anchoring devices must be able to absorb differences m movement both horizontally and vertically. If this requirement is not fulfilled, there is a risk of fatigue m the material, which usually is steel. On one hand, the device shall
hold occurring insulation pressed against the framework, with the help of a distance washer, and on the other hand it shall transmit both thrust and pull forces to the framework.
The distance between the building framework and the back side of the cavity wall may vary by several centimetres along one and the same wall. That is why these anchoring devices are supplied in different lengths, so that the tip of the wall attachment end up at the right distance from the surface of the building framework in relation to the thickness of the insulation, which normally is adapted to the wall thickness, and so that the brick tie will be able to bridge the remaining part of the distance to the back side of the cavity wall including the required embedding measurement. Often there are about ten variants of each type of wall attachment. Also, there is normally need for a number of variants of the brick tie.
The large number of variants lead to problems and rising costs with reference to distribution and stock-keeping, which affects building costs. Also there is a risk of using the wrong variant, which may lead to that anchoring devices does not comply with stipulated requirements.
PROBLEM TO BE SOLVED One object of the present invention is to provide an anchoring device with a wider range of use than earlier known devices of this kind, which makes it possible to reduce the number of variants .
THE SOLUTION
For this object, the invention is characterized in that before
mounting, the wall attachment forms a substantially flat steel bar which is provided with a series of longitudinally arranged mounting holes for attachment to the building frame, and that a corresponding series of folding notches are located m connection with these holes. By this design of the wall attachment, the length of it may easily be adapted to the actual need by bending at the appropriate folding notch, so that one and the same wall attachment covers a distance range.
According to an advantageous embodiment of the invention, the stiffening means consists of a central section forming a plane which is somewhat displaced m parallel m relationship with two side sections which are longitudinal with said section and m which central section the mounting holes are located By this design, an advantageous stiffness m flexing is achieved which may be utilised m form of a reduced thickness of material.
Preferably, the fold notches are located m the side sections and the fold notches may form V-shaped notches m said sections.
Preferably, at least one of the mounting holes is located right opposite two of the fold notches.
According to another advantageous embodiment of the invention, the width of the central section is at least about equal to the total width of the two side sections. Because the distance between the transitions of the side sections to the central section is proportionally large, an advantageous stiffness m flexing is provided. This wide central section may also be used for locating an oblong opening for attachment of a brick tie, which opening extends substantially over the entire width of the central
section. By means of this oblong, wide opening, the anchoring device is able to absorb any horizontal movements of the cavity wall .
The edges of the opening may be bent from the plane of the central section, in order to provide a contact surface towards the brick tie, which surface is larger than that which is provided by the material thickness of the sheet metal. Thereby, the risk of deformation of the hole opening is reduced, even if the material thickness is small.
According to still another advantageous embodiment of the device, one end of the wall attachment which is distant from the opening is pointed. This increases the usefulness of the wall attachment further, because it may be used for new construction of a building framework which may be built of bricks of porous concrete or hyalite blocks. For this object, the wall attachment may be prebent 90° at the first folding notch and be hammered down into the building block, so that it ends up in the horizontal joint between two blocks, that is without the need for any anchor means.
A method for mounting the device is characterized in that the wall attachment is mounted in unbent condition at the building framework, and that the wall attachment is bent substantially at right angle out from the building framework.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in the following with reference to an embodiment shown in the accompanying drawings, in which
Fig. 1 shows an anchoring device according to the invention in a position of use between a building frame and a cavity wall, Fig. 2 is a plan view of a wall attachment which is 'part of the anchoring device shown in Fig . 1 , Fig. 3 is an end view of the wall attachment,
Fig. 4 is a plan view of a distance washer which is part of the anchoring device, and Fig. 5 is a section along the line V-V in Fig. 4.
DETAILED DESCRIPTION OF THE INVENTION
The anchoring device shown in the figures comprises a wall attachment 10, a distance washer 11 and a brick tie 12. In the shown example of application, the anchoring device 10-12 is mounted between a building framework 13 and a cavity wall 14 built up at the outside of the framework.
Insulation 15 is threaded over the distance means 10 and locked into abutment against the building framework 13 by means of the distance washer 11. The brick tie 12 is then mounted in a hole opening 16 at the free end of the distance means, which mounting is performed during building of the cavity wall 14, so that both legs of the brick tie according to the art ends up in the horizontal joints below and above a building brick.
The wall attachment 10 is punched out of a comparatively thin stainless steel sheet, so that it forms a substantially flat steel bar, which is provided with a longitudinal stiffening means 17 and a series of longitudinally arranged mounting holes 18. A corres- ponding series of folding notches 19 are located in connection with these holes 18. The stiffening means 17 is composed of a
central section which forms a plane that is somewhat displaced in parallel with reference to the two side sections 20 extending along said central section. In this section the mounting holes 18 and the opening 16 are placed at the respective ends of the wall attachment. Both ends of the element are bluntly pointed, one end in order to facilitate threading of insulation, and the other end in order to enable hammering down of the prebent end into a building block, so that the element ends up in the horizontal joint between two blocks.
According to Fig. 1, a hole has been drilled for mounting into the building frame 13, after that an anchor means 21, e.g. an expansion bolt or similar, may be used for mounting the wall attachment 10 flat with the central section in abutment with the surface of the framework 13. In this, a suitable hole is selected with regard to at which distance from the framework surface the free end of the element 10 should end up. The mounting of the wall attachment to the framework is facilitated because the attachment rests flat against the framework surface.
The mounting of the wall attachment may take place well before the erection of the cavity wall. Due to that the wall attachments do not protrude out from the framework surface, the risk for damages is minimised, on one hand to the wall attachments which otherwise might have been damaged by material which may be transported along the outside of the framework, and on the other to persons that otherwise might be injured by projecting wall attachments.
When it is time to build the cavity wall 14, the wall attachment is folded outwards, substantially perpendicular to the surface of the framework, wherein folding occurs across the wall attachment,
between the two fold notches which are located nearest to the anchor means and which forms a weakening to facilitate bending. The fold notches 19 consist of V-shaped notches in the side sections 20, said notches not extending further in direction sideways than the width of the respective side section, i.e. they do not weaken the stiffening means which is formed by the raised central section 17.
Then the insulation 15 may be threaded onto the protruding, somewhat pointed end of the wall attachment. Afterwards, the distance washer 11 is pushed onto the wall attachment, which washer is provided with an I-shaped slit opening 22. This is punched out in such a way from the sheet metal, that the opening is conical with locking surfaces, so that the washer easily may be pushed onto it in one direction, but locks towards the wall attachment in the other direction. By this design of the washer, it may be pushed in to any optional position along the wall attachment, and may not glide backwards in the direction of the cavity wall . Finally, the brick tie 12 is entered through the hole opening 16 and is placed in the horizontal joints at each side of a building brick.
If the outer facing only comprises an insulation, or insulation and plastering net with plastering, the wall attachment may be used according to the above described manner without a brick tie. Also in this case, the same wall attachment may be used for a number of different insulation layer thicknesses.
The invention is not limited to the above described embodiments, but several variants are possible within the frame of the accompanying claims. For example, the wall attachment may be
designed differently than shown. Furthermore, the wall attachment may be provided with simple markings informing about which end should be pointing upwards and which side that should be turned outwards during mounting, respectively. It is also possible to design folding notches in such a way, that the outermost folding notch will be the easiest to bend, while the rest of the folding notches will be successively more difficult to bend, in the direction away from the first mentioned folding notch. By these means is insured that bending will not occur at any other folding notch than that which is closest to the attachment point at the building framework.