DE202017003133U1 - Heat resistant fastener - Google Patents

Abstract

Heat-resistant fastening element (10) for the mechanical fastening of insulating (5) and / or sealing materials (6) on flat roofs, comprising a plastic holder (12) and a screw (32), wherein the plastic holder (12) has a load-distributing head plate (14) and a hollow shaft (16) extending below the top plate (14) with a screw - in channel (18) in which the screw (32) is received in an axially countersunk manner and with its screw head (34) on a near the shaft tip (20) of the Plastic support (12) located support shoulder (25) and for the purpose of anchoring in a supporting roof substrate (1) with its threaded shank (36) from the shank tip (20) of the plastic holder (12) emerges, characterized in that on the screw (32 ) and / or on the plastic holder (12) and / or between the contact surfaces of the screw head (34) and the support shoulder (25) of the plastic holder (12) means are provided, the thermal Lock form, and / or that the screw (32) and / or the plastic holder (12) and / or the means between the screw head (34) and the support shoulder (25) are themselves at least partially made of a heat-resistant material.

Description

The invention relates to a heat-resistant fastening element for the mechanical fixation of insulating and sealing materials on flat roofs according to the preamble of claim 1.

From the prior art it is known to secure insulating and sealing materials on flat roofs mechanically against wind suction. In the mechanical fastening, in contrast to a fuse with ballast or a bond, the roof structure anchored by means of fasteners on the supporting roof substrate. For this purpose, so-called Kunststoffschraubkombinationen are preferably used, which consist of a plastic holder with molded top plate and hollow shaft and a screw inserted in the hollow shaft. The screw or its thread geometry is designed on the respective roof substrate, the e.g. made of wood, concrete or steel trapezoidal sheet may exist. While the screw used anchors in the roof substrate, the roof structure between the roof substrate and the top plate of the fastener is clamped. The load-distributing head plate of the plastic holder presses the roof seal against the insulation or roof substructure. The roof seal is, according to the current definition, the areal component for the protection of the structure, including rainwater, consisting of a water-impermeable layer extending over the entire roof area. These are usually Kunstsoff- or bitumen membranes.

From the DE 10 2012 022 325 A1 is a fastener for the mechanical attachment of insulation and sealing materials on flat roofs known comprising a plastic holder in particular of polyamide, which has a load-distributing head plate and extending below the top plate hollow shaft, both of which are penetrated by a screw. In the screw-in a screw is absorbed axially sunk, which is supported with its screw head on a near the shank tip of the plastic holder located support shoulder and exits with its threaded shaft from the shank tip of the plastic holder. The screw shaft exiting here serves as anchoring in the roof substrate and can either have a thread geometry screwing in or screwing itself into the roof material or can be used together with a dowel.

Such fasteners are also used for intermediate fixing when insulation materials are laid out of rigid polyurethane foam. High-performance insulating materials made of polyurethane, often referred to as PUR / PIR rigid foam, are much more effective than conventional insulation materials due to their extremely low thermal conductivity. Since they belong to the family of thermosets, they do not melt even at high temperatures and remain dimensionally stable and dimensionally stable. In fire protection tests, however, a s.g. Bowl effect shown. Therefore, these plates are inter-fixed, including the insulation boards are not held in the course of mechanical attachment of the roof seal on the roof surface, but also mechanically fastened below the roof seal at the edge and / or corner areas. In case of fire, the intermediate attachment of a strong tensile stress is exposed, which is caused by the described Völbbestreben the heat-acting plates made of PUR / PIR hard foam. In some cases, it could be observed that in the case of a particularly strong heat development, the screw came out of the softened holder tip, which was caused by the thermal energy introduced into the plastic holder via the screw and, in particular, the screw head.

In the DIN 18234, which deals with the structural fire protection of large-scale roofs under fire stress from the underside, is defined as a protection goal to achieve a limitation of fire propagation in the area of the closed roof surface at lower fire stress by a limited incipient fire. The term "fire propagation" is understood to mean the spread of open flames created during the fire exposure by the co-firing of components of the roof structure, which must be taken into account even after the termination of the fire stress while the glazing elements of the roof structure are still detectable.

Accordingly, it is an object of the present invention to provide a fastener for the assembly of insulating and / or sealing materials on flat roofs, which is resistant to heat. Heat resistance in this context according to the invention is to be understood that the intended use of the fastening element is ensured over a period of time corresponding to the technical rules, while retaining the function of the fastening element.

This object is achieved by a fastener with the features of claim 1. Further features of the invention are described in the dependent claims.

According to the invention, a heat-resistant fastener for the mechanical attachment of insulation and sealing materials is proposed on flat roofs, the one Includes plastic holder and a screw, wherein the plastic holder has a load-distributing head plate and extending below the top plate hollow shaft with a screw-in, in which the screw is received axially sunk. The screw is supported with its screw head on a near the stem tip of the plastic holder located support shoulder and occurs for the purpose of anchoring in a supporting roof substrate with its threaded shaft from the shank tip of the plastic holder out.

The fastening element according to the invention is characterized in that means are provided on the screw and / or on the plastic holder and / or between the contact surfaces of the screw head and the support shoulder of the plastic holder, which form a thermal barrier and / or that the screw and / or the plastic holder and / or the means between the screw head and the support shoulder itself are at least partially made of a heat-resistant material. The invention accordingly provides for stabilizing the thermally sensitive regions of the fastening element. This can be done by a modification of the individual components by means of suitable coatings or by a specific choice of material of the fastener parts themselves. The invention also provides measures which are additionally used or adapted as heat-blocking components.

The invention makes it possible to provide a fastening element for the mechanical fixation of insulating and sealing materials on flat roofs, which meets all the requirements of fire safety according to the current technical regulations. In particular, the specifications from the DIN 18234 for which a new edition will be prepared in 2017 and which provides for more specific fire safety checks than the previous ones.

According to the invention, the harmful effects of a fire in a building on which the fastening elements according to the invention are used can be averted from the fastening elements for the period required in the technical rules, so that the mechanical fastening of the insulating and sealing materials remains intact. In terms of building physics, the most diverse types of possible heat transfer are to be considered.

The standing by flames under heat roof is closed. A major influence on the fire behavior has in the present case, the conduction by the heat conduction through the contact of the different materials, here steel-plastic, takes place.

The invention is based on the finding that, in the event of a fire, the thermal conductivity of the components and materials lying in the vicinity of the fastening element, but in particular the screw tip projecting into the source of the fire, can influence the fastening quality if there is excessive softening of the fastening element used plastic holder comes in the area of the screw head seat.

A first measure according to the invention proposes various possibilities of modifications of the plastic holder.

In a particularly preferred embodiment of the invention it is provided that the granules used for the production of the plastic holder has thermally stabilizing and / or heat-resistant deposits. This has the advantage that, as a carrier material, it is also possible to use polyamide, which is outstandingly suitable for the injection molding of plastic parts.

The same applies if the granules used for the plastic holder has thermally stabilizing and / or heat-resistant granules. This ensures that even thin-walled component zones of the plastic holder remain dimensionally stable under heat, since the melting point of the material is substantially increased.

In a particularly preferred embodiment of the invention, it is provided that the granules, the Granuleinlagerungen and / or the granules consist of thermosets or thermoplastics. The latter embodiment preferably uses polyetheretherketone (PEEK) as the material for this purpose. This is a high temperature resistant thermoplastic which belongs to the group of polyaryletherketones. Its melting temperature is about 335 ° C, which allows the material to be in the liquid state, e.g. can be molded by injection molding. But also most other high temperature plastics are suitable for the production of plastic holders according to the invention. In addition, PEEK can be dyed very well without adversely affecting the physical properties.

A second measure according to the invention consists in adapting heat-resistant components on or in the plastic holder, i. to arrange or generally provide.

In a particularly preferred embodiment of the invention, it is provided that a thermally insulating protective cap is placed on the shaft tip of the plastic holder. The protected zone of the plastic holder can also be extended by a partial area or the entire hollow shaft of the holder is surrounded by a sleeve possessing the required thermal properties. This has the advantage that the conventional plastic material used for the injection molding of the plastic holder does not have to be changed. Both a protective cap and a protective sleeve are easy to install components, so that the cost price of the fasteners are not significantly increased. It is also within the meaning of the present invention, both material modifications to the plastic holder and thermally protective means to adapt. The combination of various proposed measures in each case improves the heat resistance, wherein two individual modifications in the sum can be more effective and less expensive than a single modification.

As a thermal barrier according to the invention, a washer can be used which is inserted between the screw head and support shoulder of the plastic holder tip. Both the protective cap attached to the shaft tip and / or the sleeve surrounding the holder shaft and the washer used may be made of a heat-insulating material, e.g. Ceramics, consist or have a heat-insulating coating of such a material.

Preferably, the invention further provides that the heat-insulating material is an airgel, in particular a silicate airgel. This materail has a very low thermal conductivity. Aerogels are highly porous solids, which consist of up to 98 percent air and therefore very efficiently insulate. Aerogels have approximately half the thermal conductivity compared to other comparable materials. This is only 12 to 18 milliwatts per meter and Kelvin. In contrast, the measured in mW / (m K) Wärmeleitzahl actually effective insulation boards made of polyisocyanurates (PIR) or polyurethanes (PUR) itself between 23 and 28 milliwatts per meter and Kelvin; for the commonly used expanded polystyrene (EPS) panels, between 29 and 35 milliwatts per meter and Kelvin and for extruded polystyrene foam (XPS) between 34 and 40. For mineral wool, it is between 32 and 45, for cellulose between 37 and 40 milliwatts per meter and Kelvin, and even between 40 and 50 milliwatts per meter and Kelvin for foam glass. For this reason, aerogels are increasingly used as an insulating material. With the same insulation performance, aerosol insulating materials can therefore be applied two to three times thinner than conventional insulation materials in order to achieve the required insulation effect in building renovations.

In a further preferred embodiment of the invention, it is provided that the heat-insulating material is a polyaramid or a fabric obtained therefrom. Aramids are extremely heat resistant and are considered fireproof. Their heat resistance exceeds 370 ° C. They have proven to be an asbestos substitute and are therefore usually used for the production of fire protection clothing.

According to the invention, there are numerous possibilities for the geometric configurations of a washer used for the thermal barrier.

A particularly preferred embodiment of the invention provides that the washer has a slight elevation and relative to the support shoulder of the Kunststoffhalterschaftspitze having a concave curvature. When tightening the screw, the screw head presses the washer out of the arch into a flat and plane body. If the washer is additionally provided with claws, these intersect when deforming the originally curved washer to a flat disc, in the skirt wall of the plastic holder and in the support shoulder of the stem tip. With a corresponding angular position of the claws, an additional clamping effect can be achieved, which ensures in an advantageous manner that the stem tip can not be torn off the hollow shaft at a softening of the material as a result of exposure to heat by the screw.

Another thermal protection provides an advantageous embodiment of the invention, in which the washer is formed so intrinsically stiff that the concave shape is maintained even under the tightening pressure of the screw. Here remains between the washer base and support shoulder of the plastic holder an air cushion, which significantly delays the transmission of heat transmitted through the screw heat energy.

In a particularly advantageous embodiment of the invention, it is further provided that the washer has a bottom-side hollow pipe. This surrounds the threaded shank of the screw in the region of the shaft tip, so that here a complete isolation of the screw is achieved with respect to the plastic holder. As a material or as a coating, the materials proposed for the plastic holder modifications are suitable.

The invention also proposes a further possibility in that a conventional or a modified fastener is fitted after its mounting with a fire retardant. The upwardly open screw-in channel of the plastic holder is freely accessible after the setting process and can be filled with a coolant container, which is destroyed by overheating and after releases a coolant. For this purpose, for example, a powder in a container of thermoplastic, for example, be melted at 80 ° C plastic, which thereby produces a temperature-reducing effect that the heat energy absorbed in a very short time by this and / or the screw head is thermally insulated by the powder by the trickling powder enclosing it.

The coolant container located above the screw head can also contain, as coolant, simple water and / or balls of thermoplastic synthetic material which has a melting point which lies below the material (in particular polyamide) from which the fastener is made. When a fire breaks out, which has already developed so far that the roof structure is under a strong effect of heat, the release of the coolant significantly delays the transfer of heat from the screw to the plastic holder, or by the melting thermoplastic, the heat energy from Introduced screw head into the coolant, which liquefies and dissipates the heat over a large area on the Schaftwandung.

It has been found in a preferred embodiment of the invention to be particularly advantageous when a modification is made to the screw itself. In accordance with the invention, there are preferably two starting points among other things. On the one hand, the screw portion located in the fire is protected against heat absorption and on the other hand, the screw sectors, which are in contact with the plastic, shielded against the radiation of heat. The screw sectors also include the surrounding sensitive areas of the fastening element. A partial coating of the screw can meet these requirements. Manufacturing technology, however, a coating of the entire screw is cheaper because a patielle coating usually requires a more complicated processing or handling of the screw.

A particularly preferred embodiment of the invention provides that the screw is at least partially provided with a coating forming a thermal barrier. Preferably, the entire screw is coated, although sometimes the desired effect of a thermal barrier is already achieved by the coating of the screw tip and / or the screw head.

Suitable coating materials are both known materials for screw coatings in order to use them in high temperature environments, as well as the materials proposed for the modification of the plastic holder or its adaptation parts according to the invention.

Heat-resistant materials and coatings for screws are often used in power plant construction, where there are much higher demands on the temperature resistance of components. In the present case of fire protection, on the other hand, means that form a thermal barrier for a limited time are sufficient, as longer-lasting fires either way lead to a destruction of the building.

A particularly preferred coating has proven to be a DLC coating. DLC (diamond like carbon) is a diamond-like armor-shaped carbon that has a temperature resistance of up to 350 ° C.

In addition, ceramic layers as a screw coating are also of great advantage, which can be heat resistant up to 1600 ° C.

The fastener according to the invention is therefore suitable both for use for the mechanical fastening of the roof seal, as well as for the Zwischenbefestigung of insulation materials, without including the seal with.

• 1 einen Querschnitt durch einen Dachaufbau,
• 2 das in 1 mit II gekennzeichnete Detail im Bereich eines Befestigungselementes,
• 3 einen Kunststoffhalter der vollständig aus einem hitzebeständigem Material besteht,
• 4 einen Kunststoffhalter bei dem die thermische Sperre im Bereich der Schaftspitze konzentriert ist,
• 5 eine Ausführungsform der Erfindung, bei der der Kunststoffhalter im Bereich der Schaftspitze eine Schutzkappe trägt,
• 6 einen Kunststoffhalter dessen Hohlschaft bis nahe unter die Kopfplatte mit einer hitzebeständigen Hülse umgeben ist,
• 7 das erfindungsgemäße Befestigungselement mit einer unterhalb des Schraubenkopfes eingesetzten Unterlagscheibe,
• 8 eine Variante der Erfindung mit einer Unterlegscheibe, die sich im Kunststoffhalter verkrallt,
• 9 das in 8 mit IX gekennzeichnete Detail in einer Vergrößerung,
• 10 eine Variante der Erfindung mit einer Unterlegscheibe, die eine konkave Wölbung besitzt,
• 11 das in 10 mit XI gekennzeichnete Detail in einer Vergrößerung,
• 12 eine Variante der Erfindung mit einer Unterlegscheibe, die einen bodenseitigen Hohlstutzen besitzt,
• 13 das in 12 mit XIII gekennzeichnete Detail in einer Vergrößerung,
• 14 eine Variante der Erfindung mit einer Unterlegscheibe, die eine kegelförmige Spreizhülse besitzt,
• 15 das in 14 mit XV gekennzeichnete Detail in einer Vergrößerung bei der die Scheibe und die kegelförmige Hülse in ihrer unverformten Ausgangssituation abgebildet ist,
• 16 die Scheibe und die kegelförmige Spreizhülse gemäß 14 und 15 in ihrer Montageendsituation,
• 17 eine weitere Variante der Erfindung mit einem in den Einschraubkanal eingesetzten Kühlmittelbehältnis,
• 18 das in 17 mit XVIII gekennzeichnete Detail in einer Vergrößerung,
• 19 eine weitere Variante der Erfindung bei der ein Pulver in den Einschraubkanal eingebracht wurde,
• 20 das in 19 mit XX gekennzeichnete Detail in einer Vergrößerung,
• 21 eine schematische Darstellung des Brandherdes und des Dachaufbaus und
• 22 eine schematische Darstellung der möglichen thermischen Brücken des Befestigungselementes.

The invention will be described below with reference to the drawings based on preferred embodiments. In the drawings show:

• 1 a cross section through a roof structure,
• 2 this in 1 with II marked detail in the region of a fastener,
• 3 a plastic holder made entirely of a heat-resistant material,
• 4 a plastic holder in which the thermal barrier is concentrated in the area of the shaft tip,
• 5 an embodiment of the invention, in which the plastic holder in the region of the shaft tip carries a protective cap,
• 6 a plastic holder whose hollow shaft is surrounded to near the top plate with a heat-resistant sleeve,
• 7 the fastening element according to the invention with a washer inserted below the screw head,
• 8th a variant of the invention with a washer which digs into the plastic holder,
• 9 this in 8th with IX marked detail in an enlargement,
• 10 a variant of the invention with a washer which has a concave curvature,
• 11 this in 10 with XI marked detail in an enlargement,
• 12 a variant of the invention with a washer, which has a bottom-side hollow nozzle,
• 13 this in 12 with XIII marked detail in an enlargement,
• 14 a variant of the invention with a washer which has a conical expansion sleeve,
• 15 this in 14 marked with XV detail in an enlargement in which the disc and the conical sleeve is shown in its undeformed initial situation,
• 16 the disc and the conical expansion sleeve according to 14 and 15 in their final assembly situation,
• 17 a further variant of the invention with a coolant container inserted into the screw-in channel,
• 18 this in 17 marked with XVIII detail in an enlargement,
• 19 a further variant of the invention in which a powder has been introduced into the screw-in channel,
• 20 this in 19 with XX marked detail in an enlargement,
• 21 a schematic representation of the fire and the roof structure and
• 22 a schematic representation of the possible thermal bridges of the fastener.

First, based on the 21 and the 22 the requirements for a fastener 10 be explained. Due to a fire that has broken out inside a building, there is a heat radiation from the symbolically represented fire area designated by 100. Depending on which fire propagation has been achieved, the fastener, including the supporting roof substrate and the overlying roof structure is possibly subject to extremely high heat. This can affect the properties of the unprotected plastic parts nagatively. But even a fire energy that reaches only the protruding into the fire or fire in the lead screw tip can lead by an unfavorable heat conduction to failure of the plastic part or the fastener as a whole.

In 22 the sensitive and relevant thermal bridges are reproduced. Of particular importance is the heat transfer at A1 , Here takes the drill bit 38 the heat on and passes this over the threaded shaft 36 to the plastic holder 12 further. This already happens through the convection B2 . B3 and continue over B1 in the screw head 34 , From here, more convivations act C2 . C3 , as well as a direct conduction C1 between the contact surfaces of the screw head bottom and the support shoulder 25 ,

Further heat transfer takes place via the metal vertex 4 what through the arrows A2 and A3 is indicated schematically. From here, the heat conduction takes place in the plastic holder 12 , in particular in the tip of the stem 20 by B2 and B3 , The screw transfers the heat absorbed along its threaded shaft B4 . B5 into the shaft tip of the holder.

Approximately at the dividing line marked "x", the plastic holder is characterized by two oppositely directed tensile forces " Z1 " and " Z2 "Charged. The tensile forces " Z1 "Result from the tension of the load distribution disc, while the tensile forces" Z2 "Are caused by the screw tightening force. The invention also proposes, in this context, means to effectively relieve this area.

The 1 and 2 show a cross section of a roof structure. The supporting roof substrate 1 Here is a steel trapezoidal sheet. This has alternating parallel high and low corrugations 2 . 3 , On the metal parting 4 the highsick 2 are the insulation materials used for insulation 5 on. These can be, for example, sheets of expanded polystyrene, mineral wool with compressive strength or, in some cases, large-area insulating panels of rigid polyurethane foam, which are also known as pur / pir sheets.

In 1 is in the left half of the picture, the mechanical attachment of the roofing materials 6 and the insulation material 5 shown. A first lower roofing membrane 6a becomes at its edge area 8th from the fasteners 10 penetrated by the underlying insulation board 5 and the lowest placed vapor barrier 7 pierces and is in the metal vertex 4 of the supporting roof substrate 1 anchored. The vapor barrier 7 is the layer for limiting water vapor diffusion. The mounting row is then from the parallel adjacent upper roofing membrane 6 overlaps and the seam 9 welded, creating the previously created perforation of the underlying roofing membrane 6a is sealed again.

In the right half of 1 becomes the fastener 10 for mechanical fixation of the insulation material 5 used. In this fixation called Zwischenbefestigung the insulation material 5 regardless of the roof seal below this on the supporting roof substrate 1 attached and replaced no mechanical protection against wind suction. The fastener 10 does not pierce the roofing membrane 6 . 6a but is covered by this.

In 2 This detail is reproduced in an enlarged view. The insulating material 5 is largely pressure-resistant. That is, a compression by a tread load is not possible due to the nature of the material, or occurs only to a negligible extent. The fastener 10 consists of a plastic holder 12 and a screw 32 , The plastic holder 12 includes a load-distributing head plate 14 with one below the top plate 14 extending hollow shaft 16 , The headstock 14 and the hollow shaft 16 are from a central and coaxial with the holder's longitudinal axis 13 extending screw-in channel 18 interspersed, both from the top plate 14 as well as from the top of the shaft 20 exit and in the top plate 14 an entrance opening 22 , or on the front side of the stem tip an outlet opening 23 Are defined. Approximately in the area where the stem tip 20 begins to taper, the Einschraubkanal tapers 18 with a paragraph 24 on which a support shoulder 25 is trained. The sunk in the screw 18 taken in screw 32 sits with her screw head 34 on the support shoulder 25 on. With her threaded shaft 36 kick the screw 32 from the top of the shaft 20 of the plastic holder 12 out and cuts with her drill bit 38 through the metal crown 4 of steel trapezoidal sheet. This is the screw 32 during the setting process of the fastener 10 offset by means of a screwdriver, not shown here in rotation and acted upon by an axially acting pressure force. When mounting the fastener 10 is done by means of a setting tool, the feed of the screw 32 caused by the lowering of the wrench located on the setting tool.

Like the representation of the 2 reveals the screw protrudes 32 below the metal vertex 4 a high bead 2 out. Immediately below the steel trapezoidal sheet is usually the building interior. This means that no suspended ceilings are installed here. The building interior can be used in different ways. Storage rooms are just as common uses as the establishment of production facilities or the maintenance of operating rooms with technical equipment of any kind.

If a fire breaks out inside the building, the screw tip is located directly in the fire room or even in the source of the fire. In addition to the heat transmitted via the steel trapezoidal sheet, another introduction of heat takes place in the plastic holder 12 if necessary, over the screw 32 instead of.

If a sprinkler system installed in the building, which is activated in case of fire, there is no danger to the fastener, as it is cooled by the water. In order to meet in particular the conditions according to DIN 18234 - Structural fire protection of large roofs -, it requires a corresponding modification of the fastener.

In principle, the fastening element, which is also made of plastic, must not only be heat-resistant, but also remain non-deformable when exposed to heat, ie have an adequate heat distortion resistance. Optionally, the insulating material itself may be a transmitter of thermal energy whose own heating and movement in case of fire stress the fastener.

3 shows a first variant of a heat-resistant embodiment in which the screw is not shown. The plastic holder 12a consists partly or completely of a heat-resistant material. This can be done by means of sprayable and thermally stabilizing deposits or by the use of a total heat-resistant base material.

4 shows a second variant of the heat-resistant plastic holder according to the invention 12b , Here is the thermal barrier in the area of the stem tip 20 concentrated, thanks to the use of thermally favorable particle additives 61 or the formation of the plastic holder can be achieved as a composite part. Here, the upper holder portion 62 preferably of conventional polyamide, and the lower heat-loaded holder portion 63 in accordance with the invention from a thermally highly stressable material.

The 5 shows an embodiment of the invention, in which the plastic holder 12c in the area of the shaft tip 20 a protective cap 65 wearing. This possesses in the cap floor 66 an opening so that the inserted screw with its threaded shaft from the plastic holder 12c can escape. This can be made of an unchanged polyamide plastic. It is also possible to apply both proposed measures together, ie to use a plastic holder made of a modified material and to equip this with a protective cap.

The 6 shows a plastic holder 12d whose hollow shaft 16 to near the top plate 14 with a heat-resistant sleeve 67 surrounded, whose sleeve bottom 68 is again provided for the purpose of screw passage with an opening.

Both the top of the shaft 20 of the plastic holder 12 attached protective cap 65 , as well as the hollow shaft 16 of the plastic holder 12 surrounding sleeve 67 can be made of a solid, dimensionally stable material, or even consist of a stocking-like fabric. For the latter variant refractory materials of meta-aramid fibers offer, as they are also used for fire protection clothing. But even leather can meet the requirements.

The 7 shows a preferred embodiment of the invention. The heat-resistant property is here by the use of a washer 71 causes. Alone the separation of the screw head 34 from the support shoulder 25 in the top of the shaft 20 also forms a limited thermal barrier when the washer 71 made of the same material as the screw 32 , The surface coatings of both parts alone contribute to this. However, the thermal barrier is increased abruptly when a specified material or a special coating for the washer 71 is selected. Such a thermal insulator is available in the form of many materials. These range from Teflon to aerogels, ie highly porous solids. Especially silicate aerogels show a very low thermal conductivity. Such heat-insulating materials are outstandingly suitable for the inventively proposed thermal barriers on and within the plastic holder 12 , The drill bit 38 , which is possibly located in the fire, transfers the absorbed heat through its threaded shaft 36 right up to the screw head 34 , There in the area of the support shoulder 25 lies the main transmission zone, where the thermal energy on the plastic holder 12 is transmitted. By the proposed measure, the heating of the support shoulder 25 of the plastic holder 12 advantageously decisively delayed. The materials proposed for the adaptation with the plastic holder components are suitable for the manufacture or for the coating of the washer.

The 8th shows a further development of the washer 71a , where an enlargement of the situation IX in 9 is shown. The washer 71a carries on both its peripheral wall 72 as well as on their soil 73 claw 75 that cut into the plastic holder material. The washer 71a has, before the screw is screwed into the roof substrate, a curvature, not shown here, such that the disc bottom in its unloaded initial situation relative to the support shoulder 25 of the plastic holder 12 has a concave inner camber and the washer 71a in the screw-in channel 18 of the plastic holder 12 Can be used without the claws 75 already in the holder inner wall 17 incise. Only after the screw head 34 when screwing on the top 74 the washer 71a pushes, its diameter and claws increase 75 the peripheral wall 72 cut into the holder inner wall 17 one. At the same time, the claws sting 75 of the disc bottom 73 in the support shoulder 25 of the plastic holder 12 one.

The angular position of the claws 75 on the peripheral wall 72 the washer 71a opposite the claws 75 on the disc bottom 73 are preferably selected so that the shaft wall and the shaft tip are clamped together and a tearing of the holder sections is prevented.

The 10 shows a further development of the washer 71b , where an enlargement of the situation XI in 11 is shown. The washer 71b owns opposite the support shoulder 25 of the plastic holder 12 a concave bottom 73b. The inherent rigidity of the washer 71b is designed so that even with a strong pressure by the screw head 34 the vault is preserved. Again, the same thermal protection is achieved. The drill bit 38 , which is located in the fire, transfers the heat absorbed through its threaded shaft 36 right up to the screw head 34 , There in the area of the support shoulder 25 the main thermal transfer zone lies on the plastic holder 12 , Although, despite the curvature in the underlying cavity and a transfer of heat, but this is much lower than in adjacent contact surfaces. Due to the sickle-shaped (concave) shape of the washer 71b In addition, it is achieved that the peripheral disc rim tip 81 in the ring channel 26 between support shoulder 25 and the inner wall 17 of the hollow shaft 16 cuts.

The 12 and 13 give a further advantageous embodiment of the invention again. The washer 71c has on its underside a hollow neck 76 in the screw-in channel 18 in the area of the shaft tip 20 protrudes. The hollow pipe 76 surrounds the threaded shaft 36 the screw 32 and shields this thermally against the wall of the plastic holder 12 from. In combination with the flat or curved disc portion is next to the threaded shaft and the screw head 34 isolated from the plastic holder.

The 14-16 show a particularly preferred embodiment of the invention. The washer 71d has a conical expansion sleeve 77 which are used to produce a nipple with longitudinal slots 78 is provided. This adaptation means has several advantageous properties. The washer 71d has an elevation with one opposite the support shoulder 25 the shaft tip 20 concave curvature. The disc edges carry circumferential claws 75 , which are directed in the starting position downwards. The claws 75a on the peripheral surface of the expansion sleeve 77 slide when inserting the washer in the screw 18 along the inner wall. When the screw, not shown here, is screwed into the roof base, the washer becomes 71d flattened. In the final assembly position, it is deformed into a flat disk, wherein the claws press into the holder shank wall. The same happens in the narrowed area of the screw-in channel 18 in the area of the shaft tip 20 , The cone-shaped expansion sleeve 77 is widened by the screw working through and the claws 75 a pierce the shaft top wall. In addition to the thermally blocking properties of this washer with Spreizhülsenansatz brings this embodiment of the invention has the advantage that the holder shank in the region between the upper claws 75 and the lower claws 75a can not stretch. Because in this boundary area, on the one hand, the tensile forces of Dämmstofe that try in a fire trying to pull the top plate of the plastic holder upwards. On the other hand, the tightening forces of the screw, the screw head exerts on the support shoulder directed towards the roof surface force on the shaft tip. In the case of a softening of the plastic caused by a fire, the sensitive area of the fastening element is located at this point. The proposed measure eliminates the described failure possibilities.

The 17 and 18 show a particularly advantageous embodiment of the invention. In the screw-in channel 18 of the plastic holder 12 is a coolant container 80 added. After completion of the setting process, so after the fastener 10 was mounted and the screw 32 anchored in the roof base is the screw-in 18 open and accessible until the next roofing membrane is overlapped. Before this is done, the remaining free space of the screw-in channel 18 with the coolant container 80 equipped, which permanently in the plastic holder 12 remains.

The material of the container consists for example of a at lower temperatures of preferably less than 100 ° C melting thermoplastic and is chosen so that this contacts the screw head and is destroyed in case of fire, in particular melts, and the coolant therein 85 specifically exits. For the coolant 85 it may be water or another suitable, non-flammable liquid or even beads or granules of a melting at lower temperatures, for example, 60 to 120 ° C material, such as a particular thermoplastic material, such as is used as a hot melt adhesive in hot glue guns ,

This situation is in 18 shown. The deliberately accepted and labeled 88 leakage at the coolant tank 80 should be near the screw head 34 lie. The escaping coolant 85 flows downwards and fills the screw-in channel 18 and preferably up to above the screw head 34 ,

The 19 and 20 show an embodiment of the invention, in which after the setting process, a powder 86 in the screw-in channel 18 was filled. Likewise, alternatively, the introduction of a rod-shaped end of a thermoplastic material mentioned above instead of the powder, or as a coolant container in the screw-in 18 of the holder shank possible.

LIST OF REFERENCE NUMBERS

1

supporting roof substrate (steel trapezoidal sheet)

2

High bead of 1

3

Deep bead of 1

4

Sheet metal part of 2

5

insulation materials

6

Roof sealing material

6a

Roof sealing material

7

vapor barrier

8th

Border area of 6

9

Interface of 6

10

fastener

12

Plastic holder of 10

12a

Plastic holder of 10

12b

Plastic holder of 10

12c

Plastic holder of 10

12d

Plastic holder of 10

13

holder longitudinal axis

14

Headstock of 12

16

Hollow shaft of 12

17

Holder inner wall

18

screwing passage

20

Tip of 12

22

Entrance opening of 18

23

Outlet opening of 18

24

Paragraph of 18

25

Support shoulder in 18

26

Annular channel 16

32

Screw of 10

34

Screw head of 32

36

Threaded shaft of 32

38

Drill bit of 32

61

particulate additives

62

upper holder section

63

lower holder section

65

protective cap

66

cap base

67

Sleeve of 12d

68

Sleeve bottom of 67

71

washer

71a

washer

71b

washer

71c

washer

71d

washer

72

Peripheral wall of 71

73

Bottom of 71

74

Top of 71

75

Claws of 71b ...

76

Hollow pipe of 71c

77

Expansion sleeve of 71a

78

Longitudinal slot in 77

80

Coolant container

81

Disc edge tip

85

coolant

86

powder

88

leakage

100

fire

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102012022325 A1 [0003]

Cited non-patent literature

• DIN 18234 [0010]

Claims (24)

Heat-resistant fastening element (10) for the mechanical fastening of insulating (5) and / or sealing materials (6) on flat roofs, comprising a plastic holder (12) and a screw (32), wherein the plastic holder (12) has a load-distributing head plate (14) and a hollow shaft (16) extending below the top plate (14) with a screw - in channel (18) in which the screw (32) is received in an axially countersunk manner and with its screw head (34) on a near the shaft tip (20) of the Plastic support (12) located support shoulder (25) and for the purpose of anchoring in a supporting roof substrate (1) with its threaded shank (36) from the shank tip (20) of the plastic holder (12) emerges, characterized in that on the screw (32 ) and / or on the plastic holder (12) and / or between the contact surfaces of the screw head (34) and the support shoulder (25) of the plastic holder (12) means are provided which a thermal e form a barrier, and / or that the screw (32) and / or the plastic holder (12) and / or the means between the screw head (34) and the support shoulder (25) itself are at least partially made of a heat-resistant material. Fastener after Claim 1 , characterized in that the granules used for the plastic holder manufacturing has thermally stabilizing and / or heat-resistant deposits. Fastener after Claim 1 , characterized in that the granules used for the plastic holder manufacturing has thermally stabilizing and / or heat-resistant granules. Fastening element according to one of Claims 2 and 3 , characterized in that the granules, the Granuleinlagerungen and / or the granules consist of thermosets or contain such. Fastening element according to one of Claims 2 and 3 , characterized in that the granules, the Granuleinlagerungen and / or the granule components consist of a high-temperature plastic or contain such. Fastening element according to one of Claims 2 . 3 and 5 , characterized in that the granules, the Granuleinlagerungen and / or the granule components consist of thermoplastics or contain such. Fastener after Claim 6 , characterized in that the granules, the Granuleinlagerungen and / or the granules consist of polyetheretherketone or contain such. Fastening element according to one of the preceding claims, characterized in that a thermally insulating protective cap (65) is placed on the shaft tip (20) of the plastic holder (12, 12c). Fastening element according to at least one of the preceding claims, characterized in that the hollow shaft (16) of the plastic holder (12, 12d) is surrounded by a thermally insulating sleeve (67). Fastening element according to one of the preceding claims, characterized in that between the screw head (34) and the support shoulder (25) a washer (71) is arranged. Fastener after Claim 10 , characterized in that the washer (71a) has on its peripheral wall (72) and / or at its bottom (73) claws (75). Fastening element according to one of Claims 10 or 11 , characterized in that the washer (71a, 71b) has a relative to the support shoulder (25) of the plastic holder (12) concave curvature. Fastening element according to one of Claims 10 to 12 , characterized in that the washer (71c) has a bottom-side hollow socket (76). Fastening element according to one of Claims 8 to 13 , characterized in that the washer (71), the protective cap (65) and / or the sleeve (67) consists of a heat-insulating material or is coated with such a material. Fastener after Claim 14 , characterized in that the heat-insulating material is an airgel or contains such. Fastener after Claim 15 , characterized in that the heat-insulating material is a silicate airgel or contains such. Fastener after Claim 14 , characterized in that the heat-insulating material is a polyaramid. Fastener after Claim 17 , characterized in that the heat-insulating material is a polyaramid fabric. Fastening element according to one of the preceding claims, characterized in that in the screw-in channel (18) of the plastic holder (12) above the screw head (34) a heat-destructible coolant container (80) is inserted. Fastening element according to one of the preceding claims, characterized in that the Einschraubkanal (18) of the plastic holder (12) after the setting process of the fastener (10) with a heat-resistant powder and / or a heat-liquefiable material, in particular a thermoplastic material is filled, which has a lower melting point than the material of the plastic holder (12). Fastening element according to one of the preceding claims, characterized in that the screw (32) is at least partially provided with a coating forming a thermal barrier. Fastener after Claim 21 , characterized in that the coating is a DLC coating. Fastener after Claim 21 , characterized in that the coating consists of at least one ceramic layer. Fastening element according to one of Claims 21 to 23 , characterized in that the coating is applied to the below the supporting roof substrate projecting threaded shaft (36) and / or a drill bit (38) of the screw (32).

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