The present invention relates to a device for securing a wall construction comprising an insulating layer and a net-reinforced rendering layer to a stationary wall of a building, said device comprising a securing member having an elongate stem with a central hole extending from the rear end of the stem, a locking member which includes at least one elongate element extending through at least a part of the hole in the stem, and a net fastener on which the reinforcing net is secured, said locking member being arranged to provide engagement with the building wall in order to anchor the device thereto, and the stem of the securing member being designed to extend through at least the insulting layer.

When erecting a wall construction, such as extra insulation, comprising an insulating layer, a reinforcing net and a layer of rendering supported by the reinforcing net, it is known to use devices comprising securing members, generally having a disc-shaped hat, which are placed centrally on the rear end of an elongate stem of the securing member, the whole of the stem being flexible. The reinforcing net is secured to the disc-shaped hat by means of special net fasteners so that the rendering layer, reinforcing net and securing member form a unit in the finished wall construction outside the stationary wall of the building. The rendering layer is subjected to considerable fluctuations in temperature, causing it to move in various directions. These movements cause cracks to form in the rendering, particularly around the attachment points to the reinforcing net at the securing members. Movements which may give rise to cracks at the points where the securing members are located may also occur while the rendering layer is drying. Furthermore, the weight of the rendering layer causes the securing members to bend downwards, together

with their hats and the net fasteners, which may also give rise to crack formation. Since it is the hats of the securing members that carry the weight of the rendering layer, each securing member will be subjected as a whole to consierable tensile forces, thereby causing cold creep in the plastic material so that the location of the hat in the rendering is displaced, entailing yet another reason for cracks oσcuring in the rendering layer. Although endeavours have been made to solve these problems with other types of securing devices, these have proved expensive in manufacture, complicated to assemble and time-consuming to apply on the wall of a building.

The object of the present invention is to essentially reduce the above-mentioned problem and provide a device for securing a wall construction which will permit the rendering layer to move without the stem of the securing member, but with the net fastener carried by the securing member, reproducing these movements, and which can also be produced at a lower cost, assembled in a simpler manner and applied on the wall of a building in a shorter time than can be done using known securing devices with movable net fasteners.

This is achieved according to the present invention by the stem of the securing member being provided with a lateral opening communicating with the central hole of the stem and spaced from the rear end of the stem, by the net fastener including a link arm having an inner end portion, an outer end portion and a web therebetween, by the inner end portion of the link arm being joined to said elongate element of the locking member via said lateral opening, and by the outer end portion of the link arm being arranged at a distance from the centre line of the securing member.

The invention will be described in more detail in the following with reference to the accompanying drawings.

Figure 1 shows from the side a first embodiment of a device according to the invention in assembled state prior to expansion of its engagement portion.

Figure 2 is an end view of the securing member in the device shown in Figure 1, seen from above.

Figure 3 shows the device according to Figure 1 in operative, locking position.

Figure 4 shows from the side a second embodiment of a device according to the invention in assembled state prior to expansion of its engagement portion.

Figure 5 shows the device according to Figure 4 in operative, locking position.

Figure 6 shows from the side a third embodiment of a device according to the invention in assembled state.

Referring now to Figures 1-3, these figures show a device for securing a wall construction, comprising a securing member 1 with an oblong, straight stem 2 provided at one or the forward end portion 3, with a plurality of substantially annular flanges 4, provided with sharp edges and producing a grip engagement, said flanges being arranged perpendicular to the central axis of the securing member 1. The stem 2 is provided with a central hole 5 extending axially from the rear end 6 of the stem to the forward end portion 3, becoming narrower within this and forming a conical hole portion 7 continuing into three slits 8 arranged in the forward end portion 3. The slits 8 thus extend a suitable distance from the forward end 9 of the stem, axially along the stem 1, but only

within the forward end portion 3, which can be termed the engagement portion and which is driven into an existing stationary wall of a building in order to anchor the securing member 1. Between them the slits form three axial tongues 10 which are bent radially outwards upon application of lateral forces from the inside.

The stem has a rear end portion 11 and an intermediate portion 12 located between the forward and rear end portions 3, 11. The part 5a of the hole 5 which is located within the rear end portion 11 has a larger diameter than the part 5b of the hole 5 which is located within the intermediate portion 12, so that a shoulder 13 is formed at the junction.

The device also comprises a locking member 14 comprising a free expansion pin 15 which is inserted into the hole 5 from the rear end 6 to a starting position (storage position) immediately before the engagement portion 3. ^• The length of the expansion pin 15 is such that it extends through the entire intermediate portion 12 and some way into the rear end portion 11 when in its starting position, that is to say in the state in which it is stored, and when inserted into a drill hole in the wall of a building. The locking member also includes a locking pin 16 arranged, inter alia, for driving in the expansion pin 15. The locking pin 16 is received in the hole 5 and has a head 17 which in the starting position is located outside the rear end 6 of the stem, as shown in Figure 1. The head 17 has a diameter equal to or slightly less than the diameter of the hole part 5a, and is suitably provided with grip-producing members such as flanges, around its peripheral surface so that when it is driven into locking position these will be brought into engagement with the wall of the hole.

The securing member is provided with a substantially star-shaped plate 18 (see Figure 2), arranged at the rear end 6 of the stem 2 and protruding perpendicularly from the stem 2 to be pressed against the insulting layer when the device is secured in the wall of the building.

Further, the device comprises a special net fastener 19 for application of a reinforcing net at a point spaced from the centre line of the stem. For this purpose the intermediate portion of the stem is provided with a lateral opening 20, the intermediate portion 12 being provided with an enlarged part 21 through which this lateral opening 20 extends. The hole part 5b is also enlarged within this enlarged portion 21. The net fastener 19 comprises a link arm 27 which extends through said opening and is retained with the aid of the other parts of the locking member. The link arm 27 has an inner end portion 22, provided with a hole 23 arranged to receive the expansion pin 15 when the device is in its starting position before expansion of the engagement portion 3, and also to receive the locking pin 16 when this is driven in to displace the expansion pin 15 into the engagement portion 3, as illustrated in Figures 1 and 3, respectively. The hole 23 has a larger diameter than the diameter of the expansion pin 15 and the locking pin 16 and the lateral opening 20 is sufficiently large in both axial and peripheral direction to allow the link arm 27 great freedom of movement in all directions in relation to the securing member, i.e. in axial and lateral directions, towards and away from the securing member, and in all intermediate directions. The link arm 27 also has an outer end portion 24 provided with a member to secure a reinforcing net to the link arm, such as a hole 25 through which a nail, wire or similar object of suitable design can be inserted when the reinforcing net has been attached inside or past the outer end portion 24 with the hole 25. The link arm 27 has a

straight web 26 which forms an acute angle of about 15° with the stem of the securing member. This angle may, however, vary within the interval of about 10-30°, preferably about 15-20°. The link arm 27 may suitably be produced from a metal wire which is bent to form eyes for said inner and outer end portions 22, 24 with holes 23, 25. Both link arm 27 and locking pin 16 consist of a metal material compatible with the rendering layer, usually stainless steel.

Before the device shown in Figures 1-3 is mounted, holes are drilled in the wall of the building, through the insulting layer. The diameter of drill holes shall be equal to or slightly less than the diameter of the flanges 4 on the securing member 1 so that the latter can be inserted without difficulty into the drill hole. The drill hole is sufficiently deep to allow place for the forward end portion 3 of the stem 1. The part of the stem 1 which is not inserted into the wall has a length slightly less than the thickness of the insulting layer so that the plate 18 will be in contact with the outside of the insulting layer. A slit should suitably be cut in the insulting layer to allow space for the link arm 27. To secure the securing member permanently in the wall, the locking pin 16 is hammered into the stem 2 with the aid of a hammer and punch so that the expansion body 15 is driven into the forward end portion 3 of the stem 2, effecting gradual radial expansion of the tongues 10 so that the flanges 4 press with considerable force against the hard concrete or building-stone wall of the drill hole and a strong grip is obtained in the wall of the building. The locking pin 16 now assumes the function of the expansion body 15 to retain the link arm 27, allowing a loose connection between this and the securing member. A reinforcing net, secured to each link arm 27 by suitable means as mentioned earlier, can then be applied.

Figures 4 and 5 show a second embodiment of a device for securing a wall construction, said device comprising a securing member 31, having an oblong, straight stem 32, provided at one end, the forward end portion 33, with a plurality of substantially annular flanges 34, having sharp edges and producing a grip engagement, said flanges being arranged perpendicular to the central axis of the securing member 31. The stem 32 is provided with a central hole 35 extending axially between the rear end 36 of the stem and its forward end portion 37, and having a part 35c within the extension of the end portion 33 which is somewhat less in diameter than the other parts 35a, 35b of the hole 35. Three slits 38 are arranged in the forward end portion 33, said slits extending axially a suitable distance from the forward end 37 of the stem, along the stem 32, but only within the forward end portion 33, which can be termed the engagement portion and which is driven into an existing wall of a building in order to anchor the securing member 31. Between them the slits 38 form three axial tongues 39.

The stem has a rear end portion 40 and an intermediate portion 41 located between the forward and rear end portions 33, 40. The part 35a of the hole 35 which is located within the rear end portion 40 has a larger diameter than the part 35b of the hole 35 which is located within the intermediate portion 41, so that a shoulder 42 is formed at the junction.

The device also comprises a locking member 43, comprising an oblong, straight rod 44 having circular cross section, an expansion body 46 carried by the end portion 45 of the rod, said body being axially displaceable in relation to the stem 32 of the securing member, and a turning element 47 arranged at the other end portion 48 of the rod 44. When the turning elements 47 is turned by external influence it will effect said displacement of the

expansion body 46 in relation to the stem 32 of the securing member. In the embodiment shown the rod 44 is provided with screw threading at its first end portion 45, and the expansion body 46 is therefore provided with a tapped hole 49 for screw engagement with the rod 44. The turning element 47, however, is rigidly connected to the rod in order to form a turning unit so that the expansion body 46 becomes displacable along the rod 44. Alternatively, the expansion body 46 may be rigidly connected to the rod, whereas the other end portion 48 of the rod is threaded and the turning element 47 has a tapped hole for screw engagement with the rod. As opposed to the embodiment shown in Figures 4 and 5, this alternative means that a part of the other end portion 48 of the rod will protrude freely outside the securing member 31 when the turning element 47 on the rod 44 has been screwed in.

The locking member 43 is somewhat longer than the securing member 31 so that the entire expansion body 46 will be located outside the stem 32 of the securing member when the device is fitted but in unexpended state, as illustrated in Figure 4. In the embodiment shown in Figures 4 and 5 it is the rod 44 itself which has this relatively greater length, extending suitably through the whole, or at least most of the length of the expansion body 46 when the device is assembled but in unexpended state.

The diameter of the rod 44 is somewhat less than the smallest diameter of the hole 35 in the stem, so that the rod can easily be inserted into the hole 35 from one end of the stem 32 (from the rear end 36 in the embodiment shown in Figure 4).

The expansion body 46 and the part 35c of the hole 35 located in the forward end portion 33 are so dimensioned

in relation to each other that upon insertion into the hole part 35c the expansion body will exert radial forces on the tongues 39, thus forcing them radially outwards against the hole wall of a pre-drilled hole (not shown) in the wall of the building. To enable insertion of the expansion body into the hole part 35c, either the hole part 35c or the expansion body 46, or both, is/are provided with inclined or bevelled surfaces 50, 51 extending from the forward end 37 of the stem and the forward end 52 of the expansion body 46, facing the stem 32. Generally, the expansion body 46 has at least a first portion 53 having a largest diameter which is greater than the largest diameter of the hole part 35c (which may be conical) in order to achieve a desired expansion and locking effect when the device is mounted. In the embodiment shown in Figures 4 and 5 the hole part 35c is cylindrical and has slightly greater diameter than the diameter of the rod 44, as mentioned previously, but is provided with a slight bevel extending from the forward portion 37 of the stem 32 to form said bevelled surface 51, whereas the expansion body 46 has said first portion 53, with a cylindrical part 54 and slight bevelling, which extends from the forward end 52 of the expansion body to said cylindrical part 54 in order to form said bevelled surface 50. The first portion 53 of the expansion body is at least as long as the distance between three flanges 34 on the stem 1. The cylindrical part 54 of the first portion 53 of the expansion body thus has a diameter greater than the diameter of the cylindrical hole part 35c in the stem, but of course less than the diameter of the flanges 34. The expansion body 46 is suitably provided with members 60 to prevent it turning together with the rod when the expansion body is to be drawn into the engagement portion 33. The members 60 may consist, for instance, of axial grooves and ridges on the cylindrical part 54, said grooves and ridges being

brought into engagement with inner edges on the tongues 39 or other stops means thereon.

In the embodiment shown in Figures 4 and 5 the expansion body includes a second portion 55, which has a bevelled or inclined surface 56 located nearest the first portion 53 and a cylindrical part 57 thereafter, the diameter of the cylindrical part being greater than that of the cylindrical part 54 of the first portion 53, in order to achieve reinforced expansion and locking effect upon subsequent tightening, for instance. The largest diameter of the expansion body 46 is slightly less than the diameter of the flanges 34 so as not to impede insertion of the securing member into the drill hole.

The turning element 47 may consist, for instance, of a nut as shown or of a hexagonal nut, in which case the rod 44 is preferably provided with a plate 58 in contact with the rear end 36 of the stem 32 to provide support for the nut 47 which is rigidly connected to the rod 44 in the embodiment shown.

The securing member 31 shown in Figures 4 and 5 has a substantially star-shaped plate 59, the same shape as the plate shown in Figure 2, arranged at the rear end of the stem.

Further, the device comprises a special net fastener 61 for application of a reinforcing net at a point spaced from the centre line of the stem. For this purpose the intermediate portion of the stem is provided with a lateral opening 62, the intermediate portion 41 being provided with an enlarged part 63 through which this lateral opening extends. The hole part 35b is also enlarged within this enlarged portion 63. The net fastener 61 comprises a link arm 69, which extends through said lateral opening 62 and is retained against

the securing member 31 with the aid of the other parts of the locking member. The link arm 69 has an inner end portion 64, provided with a hole 65 arranged to receive the rod 44 of the locking member 43, both when the device is in its starting position before expansion of the engagement portion 33, and when this has been expanded as illustrated in Figures 4 and 5, respectively. The diameter of the hole 65 is larger than that of the rod 44 and the lateral opening 62 is sufficiently large in both axial and peripheral direction to allow the link arm 69 great freedom of movement in all directions in relation to the securing member, i.e. in axial and lateral directions, towards and away from the securing member 31, and in all intermediate directions. The link arm 69 also has an outer end portion 66 provided with a member to secure a reinforcing net to the link arm, such as a hole 67 through which a nail, wire or similar object of suitable shape can be inserted when the reinforcing net has been attached inside or past the outer end portion 66 with the hole 67. The link arm 69 has a straight web 68 which forms an acute angle of about 15° with the stem of the securing member. This angle may, however, vary within the interval of about 10-30°, preferably about 15-20°.

Before the device shown in Figures 4 and 5 is mounted, a hole are drilled in the wall of the building, as described in connection with the first embodiment. The hole drilled in the wall should be sufficiently deep to allow place for the expansion body 46 and the forward end portion 33 of the stem 32 and a possibly protruding part of the rod 44. The part of the stem 32 which is not inserted into the wall should have a length slightly less than the thickness of the insulting layer so that the plate 59 will be in contact with the outside of the insulting layer. To secure the securing member 31 permanently in the wall, a tool is brought into engagement with the nut 47 to rotate the rod 44, thus

causing the expansion body 46 to be screwed into the forward portion 33 in the stem 32, effecting gradual radial expansion of the tongues 39 so that the flanges 34 press with considerable force against the hard concrete or building-stone wall of the drill hole and a strong grip is obtained in the wall of the building. The link arm 69 is now held by the rod 44, allowing a loose connection between this and the securing member 31. A reinforcing net, secured to each link arm 69 by suitable means as mentioned earlier, can then be applied.

Figure 6 shows a third embodiment of a device for securing a wall construction to a wood wall or a building. The device comprises a securing member 71, having an oblong, straight stem 72 with a first or forward end portion 73 and a second or rear end portion 74. As opposed to the embodiments described earlier, the stem 72 itself has no engagement portion. This function has instead been transferred to the actual locking member, as will be described below. The stem 72 has a central hole 75 running through it, and thus extending axially between its rear end 76 and its forward end 77. The part 75a of the hole 75 which is located within the rear end portion 74 is larger in diameter than the part 75b of the hole 75 which is located within the forward end portion 73, so that a shoulder 78 is formed at the junction.

The device according to Figure 6 includes a locking member 79 to attach the securing member 71 to a woodwall of a building. The locking member in this embodiment consists simply of a screw for wood," of suitable length, which is screwed in until engagement is obtained with the shoulder 78 in the hole 75.

The securing member 71 is provided with a substantially star-shaped plate 80 of the same shape as that shown in Figure 2, arranged at the rear end 76 of the stem 72.

Further, the device according to Figure 6 comprises a special net fastener 81 for application of a reinforcing net at a point spaced some distance from the centre line of the stem 72. For this purpose the forward portion of the stem is provided with a lateral opening 82, the forward end portion 73 being provided with an enlarged part 83 through which this lateral opening 82 extends. The hole part 75b is also enlarged within this enlarged portion 83. The net fastener 81 comprises a link arm 89 which extends through said lateral opening 82 and is held against the securing member 71 with the aid of the other parts of the locking member 79. The link arm 89 has an inner end portion 84, provided with a hole 85 arranged to receive the locking member 79, both when the device is in its starting (or storage) position before attachment in the wall of the building and when the device has been anchored in the wall. The hole 85 has a larger diameter than the diameter of the screw 79 and the lateral opening 82 is sufficiently large in both axial and peripheral direction to allow the link arm 89 great freedom of movement in all directions in relation to the securing member 71, i.e. in axial and lateral directions, towards and away from the securing member, and in all intermediate directions. The link arm 89 also has an outer end portion 86 provided with a member to secure a reinforcing net to the link arm 89, such as a hole 87 through which a nail, wire or similar object of suitable shape can be inserted when the reinforcing net has been attached inside or past the outer end portion 86 with the hole 87. The link arm 89 has a straight web 88 which forms an acute angle of about 15° with the stem of the securing member. This angle may, however, vary within the interval of about 10-30°, preferably about 15-20°.

No holes need generally be drilled in the wall of the building before the device according to Figure 6 is fitted. When the screw 79 for wood has been screwed into the wall of the building, a reinforcing net can be applied as described earlier.

The securing members according to the embodiments shown are relieved from tensile forces from the rendering layer in a considerable extent since the link arms, to which the nets are attached, associate to the securing members at a point located at a long distance from the rear end of the stem, and then are in engagement with an element other than the stem itself. The problem of cold creep in the plastic material is thereby essentially reduced. In order to completely eliminate the problem of cold creep, the securing member should preferably be manufactured from glassfiber-reinforced plastic material, e.g. glassfiber-reinforced nylon. A problem encountered with several known attachment means is that they are applied ^• with the aid of a hammer. The whole attachment means, together with the expansion pin, may then be hammered into the wall of the building, particularly if this is porous or if the securing member is inserted in a joint between two bricks in the wall. This problem is eliminated with the securing member according to Figures 4 and 5 since they are not subjected to any impact forces. The problem is also reduced to a great extent in the other embodiments since the enlarged part of the stem acts as a stop and prevents further axial penetration of the securing member, even in the case of porous materials.