DOUBLE-SHELL FACADE ELEMENT

Description

Field of the invention

[0001] The invention relates to a double-shell facade element comprising a flat outer glazing element and a flat inner glazing element, which are held spaced apart from one another in a thermally insulated surrounding frame profile. State of the art

[0002] In facade construction, double-skin facade systems are frequently used, with the cavity between the facades often being ventilated from behind. However, this measure reduces thermal insulation, so that double-skin facades are increasingly being constructed with an essentially closed air cushion. This design is known as a CCF facade (closed cavity facade) and has several advantages. For example, sound insulation is improved compared to double-skin, air-flow facade elements. Furthermore, there is no ingress of dirt. Finally, there is improved thermal insulation due to the insulating air cushion in the cavity between the outer and inner filling elements of the double-skin facade. However, pressure differences can occur, for example due to temperature fluctuations, so suitable measures are required to create pressure equalization. There is also a potential risk of condensation in the cavity between the facades.Condensation forms when the air in the cavity between the facade falls below the dew point.

[0003] DE 10 2013 202719 A1 describes a CCF façade with single glazing on the outside and thermally insulating glazing on the inside. A sunshade is provided in the pressure-relieved cavity between the façades. Adsorbents can be installed in the cavity to reduce the risk of condensation. The adsorbents can be regenerated by heating, which can be done using either solar radiation or an electric heater.

[0004] The double-skin glass façade element according to EP 1970525A2 also has a sunshade in the cavity between the façades and a device for at least partially dehumidifying the cavity between the façades. Document EP 3 404 190 A2 discloses a known double-skin façade element. Description of the invention

[0005] The object of the invention is to propose a facade element for a facade construction which does not require any external technology and which can ensure both pressure equalization in the system and condensation prevention in the system over an extended period of time while being highly energy efficient.

[0006] This object is achieved by a double-shell facade element having the features of one of claims 1, 9, 14 or 15. Preferred embodiments follow from the remaining claims.

[0007] The double-shell facade element according to a first aspect of the invention comprises a flat outer glazing element and a flat inner glazing element, which are held spaced apart in a thermally insulated surrounding frame profile, at least one pressure equalization device that is in air-conducting communication with the outside atmosphere and with a facade gap provided between the outer glazing element and the inner glazing element, and at least one drying device that can be filled with desiccant and is integrated either in the facade gap or in the surrounding frame profile and is in air exchange with the facade gap. Furthermore, at least one capillary element is provided, which is a component of the surrounding frame profile and is preferably partially formed by a section of the surrounding frame profile.The pressure equalization device and the drying device are arranged and dimensioned such that they do not extend into a transparent area of ​​the planar outer glazing element and the planar inner glazing element, i.e., they are not located in a transparent area of ​​the planar outer glazing element and the planar inner glazing element. The at least one drying device is designed to enable an exchange of the desiccant and preferably comprises an exchange opening designed to enable the exchange of the desiccant toward the room side.

[0008] The room side refers to the installation position of the facade element and is located on the side of the interior glazing facing away from the facade cavity. The transparent area of ​​the exterior glazing element and interior glazing element is understood to be the area within which an observer can see through the main planes of the exterior glazing element and interior glazing element in a viewing direction perpendicular to them, because in this area both the exterior glazing element and the interior glazing element are not covered by other components such as sealing strips. The dimensioning and arrangement of the pressure equalization device and drying device according to the invention thus has the advantage that they are fully integrated into the area of ​​the surrounding frame profile and are therefore completely concealed from an outside observer.

[0009] The air exchange between the drying device and the façade cavity can take place either by the pressure equalization device interacting with the drying device and thus the drying device as well as the pressure equalization device being integrated into the air-conducting connection between the outside atmosphere and the façade cavity, or by a direct air exchange between the façade cavity and the drying device parallel to the air-conducting connection between the outside atmosphere and the façade cavity.

[0010] The term "component of the surrounding frame profile" means that the capillary element already forms a pre-assembled unit with the surrounding frame profile and no longer needs to be installed separately when constructing a facade.

[0011] A capillary element is characterized by an internal cavity whose cross-sectional dimensions are significantly smaller than its length. The internal cavity need not have a constant cross-section along its length, nor a linear longitudinal extension. The capillary element serves to equalize pressure.

[0012] The facade element according to the invention incorporates all essential properties in a system-inherent manner. No external technology is required to establish pressure equalization within the system. The pressure equalization within the system can be designed to inhibit moisture ingress, be watertight, dustproof, and / or dampen pressure amplitudes. Furthermore, the provision of the pressure equalization device and the drying device prevents condensation within the system. The pressure equalization device can be fully integrated into the surrounding frame profile, so that no visible projections or air ducts are required outside the facade element. Furthermore, the double-skin facade element is highly energy efficient in both winter and summer.In winter, the excellent thermal insulation comes into play, and in summer, material temperatures of no more than 80°C can be achieved in the façade cavity, preventing fogging when using materials with potentially volatile components. This contributes to compliance with comfort criteria in summer. Compliance with the comfort criteria also depends on the energy transmittance between the façade cavity and the interior of the room and is particularly influenced by the flat interior glazing element and the thermal break of the surrounding frame profile. An optional sun protection system installed in the façade cavity also contributes to compliance with the interior comfort criteria.

[0013] Thus, according to a preferred embodiment, the at least one capillary element can comprise a membrane with a capillary tube, wherein the capillary tube has a length of at most 60 mm and preferably of at most 20 mm, and particularly preferably of at most 10 mm, and an inner diameter of at most 1.5 mm and preferably of at most 1.0 mm. Such a so-called short capillary tube is marketed, for example, by the company Swisspacer. The mode of operation is described in WO2019 / 110409 A1. A short capillary tube is preferably arranged in the region of the pressure relief openings. A short capillary tube can be provided both in interaction with the drying device and without interaction with the drying device.

[0014] Alternatively, according to a preferred embodiment, the at least one capillary element can comprise a capillary tube having a length of at least 200 mm and optionally having a membrane, a filter, or a sieve at the opening of the capillary tube to the outside environment. A capillary tube with the dimensions mentioned is referred to below as a long capillary tube. A long capillary tube can be provided as a separate component and made of glass or metal, preferably aluminum or hard or flexible plastic.

[0015] When long capillary tubes are provided, they have a clear cross-section of less than 1 mm 2 , preferably less than 2 mm 2 , more preferably less than 4 mm 2 , and most preferably less than 6 mm 2 . The length of the capillary tube and the clear cross-section of the capillary tube are coordinated. An increasing capillary tube length allows for an increasing clear cross-section.

[0016] The shape of the clear cross-section can be chosen arbitrarily. However, it is preferably circular, semicircular, square, rectangular, triangular, diamond-shaped, or elliptical.

[0017] The wall thickness of a long capillary tube provided as a separate component is between 0.5mm and 5mm and is preferably a maximum of 2mm.

[0018] When using a long capillary tube, a membrane or filter can be provided in the area of ​​the pressure relief opening. The length of a long capillary tube can be selected depending on the orientation, up to the width, height, or circumference of the facade element. The basic rule for a pressure equalization device with a long capillary tube is that the inlet opening of the capillary tube is connected to the outside atmosphere. The outlet opening of the capillary tube is connected to the facade cavity, either without interaction with the drying device or with interaction with the drying device. The inlet opening can be arranged on the surrounding frame, either in the area of ​​a main frame profile or a sub-frame profile towards the expansion joint, and is advantageously arranged so that it is protected against water ingress.

[0019] The design of a long capillary tube depends on the location of the building and the prevailing weather data in the form of outside temperature, air pressure, relative humidity, and solar radiation intensity, which can be generated hourly for a defined location worldwide using the Meteonorm software. The temperature in the cavity depends on the pane structure, the energy absorption coefficients of the individual panes, the use of sun protection, the intensity of solar radiation, and the air temperatures outside and inside the building. It can be calculated for each hour from the weather data based on EN 16612:2019, Annex C. A capillary tube represents a flow resistance to the incoming or outgoing air, which is incorporated into the calculation model via the capillary inner diameter and capillary length.Using the calculation model, the moisture transport is determined via the volume flow through the capillary tube. The volume flow through the capillary tube is assumed to be directly proportional to the applied pressure difference.

[0020] The volume flow through each capillary tube of a facade element according to the invention, depending on the hourly weather data, can be used to estimate the amount of water vapor that penetrates from the outside atmosphere into the facade cavity via the capillary tubes and is adsorbed by the desiccant over a defined period of time, e.g. one year.

[0021] According to a preferred embodiment, the capillary element comprises a capillary tube which is fully integrated into the surrounding frame profile of the facade element, preferably clipped into the surrounding frame profile.

[0022] According to an alternative preferred embodiment, the drying device comprises a desiccant container, and the at least one capillary element comprises a capillary tube which is integrated into the desiccant container.

[0023] According to an alternative preferred embodiment, the drying device comprises a desiccant container, and the at least one capillary element comprises a capillary tube formed from a groove in the desiccant container and a wall of the surrounding frame profile.

[0024] A further preferred embodiment of the double-shell facade element is characterized in that the capillary element comprises a groove in the surrounding frame profile and a plastic end profile, with a cavity formed between the end profile and at least one inner wall of the groove. The groove can be provided in the subframe profile or in the main frame profile in partial areas or over the entire circumference of the respective frame profile.

[0025] The end profile is made of a thermoplastic material or an elastomer with increased vapor resistance. Preferred materials are EPDM, butyl, polytetrafluoroethylene, or polyvinylidene fluoride.

[0026] Alternatively, open-cell foam bodies can be provided as a valve and sieve in conjunction with the desiccant in the area of ​​the drying device.

[0027] A further alternative design of the at least one pressure equalization device is that it is provided as a capillary tube integrated in the main frame profile in partial areas or in the entire circumference of the main frame profile.

[0028] A further alternative design of the at least one pressure equalization device is as a capillary tube which is integrated in the subframe profile of the facade element in partial areas or in the entire circumference of the subframe profile.

[0029] Preferably, the at least one pressure equalization device comprises an elastic profile with at least one opening, which forms part of an air-conducting connection path between the facade cavity and the outside atmosphere.

[0030] Finally, when providing a capillary tube, it is possible to design the opening to the outside climate at a high level, ie with the inlet opening at the top to the outside climate in a vertical frame part of the surrounding frame profile.

[0031] If a short capillary tube is used, plastic or metal can be used as the material for the capillary tube. Aluminum is preferred. If a long capillary tube is used, it can be made of glass, metal, preferably aluminum, or plastic, preferably an elastomer such as polyethylene, polypropylene, polyvinylidene fluoride, or ethylene-propylene copolymer.

[0032] According to a second aspect of the invention, the double-shell facade element comprises a flat outer glazing element and a flat inner glazing element, which are held at a distance from one another in a thermally insulated surrounding frame profile; at least one pressure equalization device which is in air-conducting connection to the outside atmosphere and to a facade gap provided between the outer glazing element and the inner glazing element; and at least one drying device which can be filled with desiccant and which is either arranged in the facade gap or integrated in the surrounding frame profile and is in air-conducting connection to the facade gap, wherein the double-shell facade element further comprises means for reducing vapor diffusion,The means for reducing vapor diffusion comprise wet glazing and / or at least one insulating web for thermal separation in the thermally insulated surrounding frame profile made of a plastic with high vapor impermeability and / or with a coating material with high vapor impermeability. The pressure equalization device and the drying device are arranged and dimensioned such that they do not extend into a transparent area of ​​the planar outer glazing element and the planar inner glazing element. The drying device is designed to enable an exchange of the desiccant and preferably comprises an exchange opening designed to enable the exchange of the desiccant toward the room side.

[0033] Examples of an insulating strip with a coating material with high vapor impermeability are the application of a vapor-tight or highly vapor-retardant film made of thin stainless steel on the plastic insulating strip or the application of a metal-coated plastic film or butyl film on the plastic insulating strip or the provision of an insulating strip made of a metal-coated plastic.

[0034] When providing an insulating web made of a plastic with high vapor tightness, polyvinylidene fluoride can advantageously be used as the material for the insulating web.

[0035] In the case of a double-shell facade element according to the second aspect, the at least one pressure compensation device can also comprise a capillary element.

[0036] Likewise, in a double-shell facade element according to the second aspect, an opening in one of the at least one pressure equalization device can be in flow connection with a second opening in a cavity of one of the at least one drying device that can be filled with desiccant.

[0037] Preferably, the drying device comprises a desiccant container that can be filled with desiccant and that can be detachably fastened to the surrounding frame profile.

[0038] According to a third aspect of the invention, the double-shell facade element comprises a flat outer glazing element and a flat inner glazing element, which are held spaced apart in a thermally insulated surrounding frame profile; at least one pressure equalization device, which is in air-conducting connection to the outside atmosphere and to a facade gap provided between the outer glazing element and the inner glazing element, and comprises an air guiding device; wherein the pressure loss of the air flow during pressure equalization is determinable and preferably adjustable by the length and / or the cross-sectional dimensions of the air guiding device and / or the number of deflections of an air flow flowing through the air guiding device;at least one drying device that can be filled with a desiccant bed and is integrated into the surrounding frame profile, wherein the at least one drying device comprises at least one first opening that is in air-conducting connection to the facade cavity; the at least one pressure equalization device and the at least one drying device are arranged and dimensioned such that they do not extend into a transparent area of ​​the facade element, and the drying device is designed to enable an exchange of the desiccant and preferably comprises an exchange opening that is designed to enable the exchange of the desiccant in the direction of the room side.

[0039] Even with this alternative design, no external technology is required to achieve pressure equalization within the system. The pressure equalization within the system can be designed to prevent moisture ingress, be watertight, dustproof, and / or dampen pressure amplitudes. Furthermore, the provision of the pressure equalization device and the drying device prevents condensation within the system. The pressure equalization device can be fully integrated into the surrounding frame profile, thus eliminating the need for any visible protrusions or air ducts outside the facade element.

[0040] In this alternative design of the facade element according to the invention, the use of a separately provided capillary tube is dispensed with and instead the air flow that creates pressure equalization is guided through an air guiding device, via the geometry of which the pressure loss of the incoming or outgoing air that occurs as a flow loss can be determined.

[0041] According to a fourth aspect of the invention, the double-shell facade element comprises a flat outer glazing element and a flat inner glazing element, which are held at a distance from one another in a thermally insulated surrounding frame profile; at least one pressure equalization device, which comprises an air guiding device and is in air-conducting connection to the outside atmosphere and to a facade gap provided between the outer glazing element and the inner glazing element; and at least one drying device, which can be filled with a desiccant bed and is integrated in the surrounding frame profile, wherein the at least one drying device comprises at least one first opening, which is in air-conducting connection to the facade gap, and at least one second opening, which is in air-conducting connection to the air guiding device;the pressure loss of the air flow during pressure equalization is determinable and preferably adjustable by the pressure loss during flow through the at least one drying device and the at least one air guiding device; the at least one pressure equalization device and the at least one drying device are arranged and dimensioned such that they do not extend into a transparent region of the facade element; and the at least one drying device is designed to enable an exchange of the desiccant and preferably comprises an exchange opening designed to enable the exchange of the desiccant in the direction of the room side.

[0042] In this alternative design of the facade element according to the invention, the use of a separately provided capillary tube is dispensed with and instead the air flow that creates the pressure equalization is guided through the drying device and the path of the air flow through the desiccant bed is selected so that on the one hand the pressure loss is not too high in order to prevent air exchange when pressure differences occur, but on the other hand the air flow flows through the desiccant bed over the longest possible path when pressure equalization occurs in order to load the desiccant as evenly as possible and thus increase the service life until the desiccant is replaced.An air-conducting connection can be either a direct connection or an indirect connection. With a direct connection, for example, the first opening opens directly into the cavity between the facade and / or the second opening connects the interior of the drying device with the air ducting device. With an indirect connection, additional elements can be inserted in between, such as a filter. Since the cost of capillary tubes increases the manufacturing costs of double-skin facade elements and additional costs are incurred for the maintenance and servicing of capillary tubes, facade elements without the use of capillary tubes represent a considerable simplification and improvement. However, with an increased flow through the desiccant, the loading rate of the desiccant increases and, for a given mass of desiccant, the time interval until the moisture-laden desiccant needs to be replaced decreases.Therefore, in this case, additional measures are useful to reduce moisture ingress.

[0043] Preferably, the desiccant consumption can be determined depending on the location of the facade element integrated into a facade, the type of desiccant and the design features of the facade element.

[0044] However, it is essential when designing the double-skin façade element without a capillary tube that a sufficient amount of desiccant is provided which prevents condensation in the façade cavity at a preselected desiccant exchange time, which is only possible if, at a given location and the climatic conditions prevailing there, the desiccant is exchanged at the latest when it is fully loaded with water.

[0045] The required amount of desiccant is therefore preferably calculated based on the location of the building in which the double-skin facade element according to the invention is to be installed, as well as the orientation of the facade, which has a significant influence on solar radiation. Worldwide, the weather data prevailing at a location can be generated hourly using the Meteonorm software. The weather data includes the outside temperature, air pressure, relative humidity, and the intensity of solar radiation. The temperature in the cavity depends on the pane structure, the energy absorption coefficients of the individual panes, the use of sun protection, solar radiation, and the air temperatures inside and outside the building. It can be calculated from the weather data for every hour of the year based on EN 166612:2019, Annex C.

[0046] In this way, it is possible to estimate the amount of water vapor that flows from the outside atmosphere into the façade cavity with the volume flow of air during pressure equalization over a defined period of time, e.g. one year. This amount of water vapor must be adsorbed by the desiccant. If the desiccant is to be replaced every 10 years, for example, a sufficient amount of desiccant must be provided so that the amount of water vapor transported into the façade cavity with the air flow during pressure equalization over a period of 10 years can be adsorbed in the desiccant until it is replaced with regenerated or fresh, unloaded desiccant. The maximum amount of water vapor that can be absorbed by a specific desiccant, e.g. a specific zeolite material, per unit mass is known for individual desiccants. A suitable calculation model was developed by ift Rosenheim.

[0047] Once the calculations described above have been carried out for a specific location, the required quantity of desiccant can be easily derived from the existing calculations in the case of different structures of the double-skin façade element, for example a smaller volume of the façade cavity with modified dimensions of the façade element, because the air flow flowing into the façade cavity during pressure equalization and thus also the water vapor to be absorbed by the desiccant is proportional to the volume of the façade cavity.

[0048] Alternatively, a standard facade element can be provided and the resulting desiccant exchange time can be adjusted using the above calculation depending on the location and orientation of the destination of the double-skin facade element.

[0049] If pressure equalization becomes too low, it may be necessary to limit the pressure loss / flow resistance. When air is directed through the desiccant filling, this necessarily means that the path through the desiccant filling must be shortened. In addition to the previously described embodiments with at least a second opening into the desiccant container at half height, it may also be necessary to limit the path through the desiccant by reducing the filling height of the desiccant filling. This then has the desired effect of lower pressure losses / lower flow losses, but at the same time also results in larger weather-related air volumes—and thus larger amounts of moisture—and thus greater desiccant consumption.This is acceptable as long as the intentionally reduced desiccant supply has a reasonable lifetime until the desiccant supply is fully charged, thus allowing a specified replacement interval for the desiccant supply to be maintained. Reducing the path through the desiccant by reducing the desiccant fill level therefore triggers two effects. The basis for this optimization task is again the measurement of the volume flow through the desiccant as a function of the applied pressure and thus also of the pressure loss. This data must then be converted into weather-dependent values ​​for desiccant consumption, as described above.

[0050] According to a preferred embodiment, the air guiding device comprises deflection elements that create a winding air flow path through the air guiding device. A flow path with multiple deflections for changing the direction of the airflow serves, on the one hand, to increase the pressure loss; on the other hand, the deflections can also serve as inertial separators for dust entrained in the airflow, preventing it from entering the cavity between the facades. Another advantage of this measure is that it eliminates the need for filters, sieves, or membranes in the airflow path.

[0051] Preferably, the at least one drying device is integrated into cavities of the elements of the surrounding frame profile, which are arranged vertically in the installed position. This optimizes the available installation space and ensures that the drying device is not visible even when viewed from a direction that deviates from a direction perpendicular to the main plane of the glass elements.

[0052] In addition, according to a preferred embodiment, the at least one drying device can be integrated both into cavities of the elements of the surrounding frame profile arranged vertically in the installation position and into cavities of the elements of the surrounding frame profile arranged horizontally in the installation position.

[0053] In the designs according to the third aspect and the fourth aspect of the invention, the double-shell facade element can also further comprise means for reducing vapor diffusion, wherein the means for reducing vapor diffusion comprise wet glazing and / or at least one insulating web for thermal separation in the thermally insulated surrounding frame profile made of a plastic with high vapor impermeability and / or with a coating material with high vapor impermeability.

[0054] In all alternative designs of the double-shell facade element according to the invention, a cover can advantageously be provided which can be fastened to the surrounding frame profile and is preferably screwed or clipped onto the sub-frame profile.

[0055] This cover, which can be attached to the surrounding frame profile, is preferably made of a plastic with water adsorption capacity. In this way, a portion of the water vapor carried along when air flows from the outside atmosphere into the façade cavity is adsorbed in the plastic material of the cover and desorbed from the cover material when dried air flows out of the façade cavity into the outside atmosphere. This reduces the moisture ingress into the façade cavity, thereby increasing the service life of the desiccant.

[0056] All alternative solutions according to the invention ensure condensation prevention in the system over an extended period of time. The provision of means to reduce vapor diffusion delays the entry of water vapor into the façade cavity, as does the provision of a capillary element, which can be part of the pressure equalization device and simultaneously serves the function of reducing the entry of water vapor into the façade cavity. Both measures, which can be implemented individually or in combination, extend the period until the adsorbents in the drying device are exhausted, since the adsorbents can bind a defined amount of water before they must be replaced and regenerated either under reduced pressure or at elevated temperatures.

[0057] The self-contained, pressure-relieved facade element according to the invention is a double-skin facade element, preferably constructed as a sub-element of a prefabricated facade. The basic concept consists of combining a double-skin facade element with a pressure equalization device and a drying device.

[0058] The pressure equalization devices preferably have at least one of the following properties: vapor diffusion inhibiting, watertight, dustproof, and pressure amplitude damping. Various designs are possible to achieve these properties individually or in combination.

[0059] According to a preferred embodiment of the invention, the surrounding frame profile comprises a main frame profile and a subframe profile, wherein the main frame profile and the subframe profile are detachably connected to one another via connecting means, and the subframe profile holds the external glazing element. In this way, the double-shell facade element comprising the at least one pressure equalization device and the at least one drying device fillable with desiccant can be opened in the assembled state, for example, to install the sun protection.

[0060] The seal between the main frame profile and the subframe profile should preferably be vapor-tight. "Vapor-tight" means that the sealing material has only negligible vapor permeability. An example of a suitable material is thermoplastic butyl.

[0061] Preferably, the at least one pressure compensation device is arranged in the main frame profile or in the subframe profile.

[0062] Preferably, the double-shell facade element comprises at least one sun protection device in the facade cavity between the exterior glazing element and the interior glazing element. The sun protection device is preferably designed to be adaptive.

[0063] The provision of sun protection devices serves to increase comfort in summer, but also in winter when the sun is low in the sky. Furthermore, thermal insulation can be influenced by adjusting the proportion of radiation and convection.

[0064] According to a preferred embodiment, the interior glazing element comprises either multi-pane insulating glass, preferably with two or three glass panes, or vacuum insulating glass. The interior multi-pane insulating glass preferably has U-values ​​of 0.5 to 1.4 W / (m 2 < K). Alternatively, vacuum insulating glass with U-values ​​of 0.7 W / (m 2 < K) and less can be provided. The thermal insulation of the surrounding frame profile is located in the area of ​​the thermally insulated interior glazing. From a structural physics perspective, it is important that the surrounding frame is not thermally insulated in the area of ​​the exterior glazing, as otherwise, condensation problems would increase in position 2 of the exterior glazing.

[0065] Furthermore, the external glazing element is preferably provided as a monoglass, preferably as laminated glass or laminated safety glass, and preferably comprises at least one functional layer, particularly preferably a wavelength-selective coating.

[0066] Alternatively or additionally, additional functional layers can also be provided, such as solar and / or thermal protection layers. Examples of a wavelength-selective coating include an LE layer or a switchable layer. It is particularly advantageous to provide solar and / or thermal protection layers on the surfaces commonly referred to as positions 1 and / or 2. If functional layers are provided on positions 1 or 2, they can be applied over the entire surface or in partial areas. In the same way, it is also possible to provide double-glazed units on the outside and, if necessary, also provide them with functional layers, in particular solar and / or thermal protection layers.

[0067] The double-shell glass construction features a comprehensive, thermally insulated metal enclosing frame profile. The enclosing frame profile is preferably made of aluminum, and can particularly preferably be provided with hollow chambers. The enclosing frame profile should be largely vapor-tight. Various measures can be taken individually or in combination to achieve this, particularly measures on the insulating bars. The insulating bars are preferably provided with a vapor-tight or highly vapor-retardant film applied all the way around them. To improve the vapor-tightness of the entire enclosing frame profile, this film is also wrapped around the mitered corners of the enclosing frame profile, simultaneously sealing the mitered corner bond. The area of ​​the glazing integration can be sealed with suitable sealants.

[0068] Preferably, an air-conducting connection path is provided between the at least one pressure equalization device and the facade gap, which preferably comprises a filter element.

[0069] Preferably, an opening in one of the at least one pressure equalization device is in flow connection with a second opening in a cavity of one of the at least one drying device that can be filled with desiccant.

[0070] Preferably, the drying device comprises a cavity that can be filled with desiccant, which is an integral part of the surrounding frame profile and has a replacement opening that is designed to enable replacement of the desiccant.

[0071] Preferably, the pressure equalization device comprises a cavity which comprises an opening into the façade cavity, and the cavity is filled with desiccant.

[0072] Preferably, the at least one pressure equalization device comprises an elastic profile with at least one opening arranged in an air-conducting connection path between the facade cavity and the outside atmosphere.

[0073] According to a preferred embodiment of the invention, the double-shell facade element comprises an opaque inner element and an outer element, which are held at a distance from each other. The outer element can also be opaque. However, according to a preferred embodiment, the outer element is transparent.

[0074] According to an advantageous embodiment, the opaque inner element and the transparent outer element can be held in an additional surrounding frame profile. This embodiment represents a so-called "shadow box."

[0075] The optionally provided opaque elements are preferably arranged in the parapet area and can be configured as glass elements or as panel or sheet metal elements. If the transparent elements are provided as glass elements, they can be configured as mono-glass, laminated glass, laminated safety glass, or double-pane insulating glass, and can be coated either externally or internally or colored within the body to create the desired properties. If a panel or sheet metal element is provided, thermal insulation is preferably provided on the inside.

[0076] When providing a room-side panel, the transparent area and opaque area can be arranged in the surrounding frame profile. Alternatively, two separate surrounding frame profiles can be provided, with the surrounding frame profile for the transparent area and another surrounding frame profile for the opaque area. The thermal insulation of the additional surrounding frame profile is preferably located in the area of ​​the glass panes or the panel. When providing sheet metal elements, internal thermal insulation is preferred.

[0077] Preferably, all components are accessible and thus maintainable, repairable, and replaceable. This also applies to any optional sun protection. However, it is also particularly preferred to design the facade elements so that the pressure equalization device and the glass panes are equally accessible and thus replaceable.

[0078] The pressure equalization device with moisture ingress limitation can be designed according to requirements and thus adapted to local climatic conditions such as solar radiation, outside air temperature and wind loads.

[0079] The drying device serves to provide additional security to the pressure equalization device that limits moisture ingress. The volume of desiccant used is based on the desiccant's adsorption capacity, i.e., the maximum amount of water vapor that can be absorbed per unit volume of desiccant. Furthermore, the desiccant volume also depends on how effectively the pressure equalization device limits moisture ingress. Finally, the local climatic conditions and the enclosed volume of the cavity between the facades must also be considered.

[0080] The pressure equalization device and the drying device can work together. If no interaction between the pressure equalization device and the drying device is desired, the pressure equalization device can be installed in a separate hollow chamber next to the drying device, directly connected to the facade cavity, in the subframe profile or the main frame profile. Alternatively, the pressure equalization device can be installed in the main frame profile or subframe profile without any flow connection to the drying device.

[0081] If the pressure equalization device and the drying device are to be integrated, this can be done either without direct physical contact between the pressure equalization device and the drying device, or with direct physical contact between the pressure equalization device and the drying device. If no physical contact is to be made between the pressure equalization device and the drying device, this can be done with or without piping. If direct physical contact between the pressure equalization device and the drying device is to be provided, the pressure equalization device can be installed either in the main frame profile or subframe profile, or in the desiccant container.

[0082] The pressure equalization device can be arranged in the horizontal surrounding frame profile and / or in the vertical surrounding frame profile. If the pressure equalization device is arranged in the horizontal surrounding frame profile, it is located either externally in the subframe profile at the bottom and / or top and / or side. The number of pressure equalization devices should be provided as required. If multiple pressure equalization devices are provided, they are preferably arranged offset from one another.

[0083] This also applies if the pressure compensation device is arranged in the vertical main frame profile on one side and / or both sides. One or more pressure compensation devices can be provided, and if multiple pressure compensation devices are provided, they are preferably arranged offset from one another.

[0084] If the pressure equalization devices are located in both the horizontal main frame profile and the vertical frame profile, they are arranged either horizontally at the bottom plus vertically on one or both sides, or horizontally at the top plus vertically on one or both sides. Alternatively, the pressure equalization devices can also be arranged on all sides of the main frame profile.

[0085] The number of pressure equalization devices depends on the requirements. The key factors here are the volume of the cavity between the facades and the local climatic conditions, taking into account the orientation of the facade.

[0086] The drying devices with desiccant contain a moisture-adsorbing substance to help prevent condensation. Examples include silica gel or zeolite-based adsorbents. The drying devices are located in hollow chambers of the frame profiles or in separate containers. If the drying devices with desiccant are located in hollow chambers of the frame profiles, they can be arranged in a hollow chamber in the sub-frame profile and / or main frame profile, in some areas or in all hollow chambers. If the drying devices are provided in separate containers, they can be arranged either in the façade cavity between the glass elements on the outside and inside and attached to some areas or to all parts of the surrounding frame. Alternatively, drying devices with separate containers can also be arranged in the parapet area of ​​the façade elements and connected to the façade cavity via an air-conducting system.

[0087] The desiccant can be replaced in a variety of ways. Firstly, the desiccant can be sucked out of the cavities in the frame profiles from the inside or outside and reinserted with new material or, after regeneration following appropriate treatment by desorption of water vapor, reinserted by blowing it back in. If the opening is located at the bottom, it is possible to drain the exhausted desiccant under the influence of gravity. Particularly preferred is replacing the desiccant through resealable openings in the frame profiles. Finally, it is also possible to completely replace containers with exhausted desiccant. This is done by removing the container after dismantling or opening glass panes to access the space between the facades and either immediately replacing it with a new container or reinserting the container after regeneration of the desiccant it contains.

[0088] Preferably, the external glazing element is removed, but with a corresponding design of the surrounding frame profile, it is also possible to remove the internal glazing element, for example by removing an internal glazing bead.

[0089] There are various options for making the façade cavity accessible from the outside and / or inside. Firstly, the inner and / or outer glass elements can be removed. Alternatively, depending on the façade construction, it might also be possible to open either the inner or outer glass elements. For example, a casement window could be provided that can be opened by unlocking a pivoting fitting. Access to the glass elements is possible after the glazing beads or pressure strips have been removed.

[0090] If the outer glass pane is not held in place by a glazing bead but is firmly attached to the subframe profile, the outer glass element can be removed by loosening the screw connection that secures the subframe profile to the main frame profile. If a hook-in technique is used to connect the subframe profile to the main frame profile, the subframe profile can be removed from the main frame profile.

[0091] Access to the façade cavity is advantageous for replacing damaged glass panes and for cleaning components and surfaces in the façade cavity. Another purpose is to be able to maintain, repair, or replace components in the façade cavity. This includes, in particular, an optional sun protection device, a drying system, and components of the pressure equalization devices.

[0092] The facade element according to the invention is largely vapor-tight. Various measures are provided for this purpose. On the one hand, wet glazing of the glass panes inside and outside with the surrounding frame can be provided. If necessary, a butyl sealant interlayer can be provided to improve vapor tightness. Another measure for achieving high vapor tightness consists in providing vapor diffusion-reducing measures on one or both insulating webs for thermal separation. For example, thin stainless steel foils with a thickness of no more than 0.050 mm or metal-coated plastic films can be used. Alternatively, plastics with high vapor tightness such as butyl or polyvinylidene fluoride can be used for the insulating webs, or such a plastic can be applied to the surface of the insulating webs by coextrusion.The insulation bars can also be made entirely of a plastic with high vapor-tightness, such as polyvinylidene fluoride. Another alternative or supplementary measure to improve vapor-tightness is to seal penetrations and / or additionally seal frame corner connectors. Sealants or glued-on foils can be used, as described in connection with the insulation bars. For this purpose, a vapor-diffusion-inhibiting foil can be applied all the way around the interior or exterior insulation bar after the frame profile has been manufactured, which also seals the mitered corners.

[0093] The most preferred measure to increase vapor tightness is the application of a butyl layer to the insulation bars, preferably from the outside.

[0094] According to a preferred embodiment of the double-shell facade element, the pressure equalization device and the drying device in the facade cavity are accessible by opening or removing the outer glazing element or an opaque outer element, or the inner glazing element or an opaque parapet element. In other words, by removing or opening the glazing element or panel arranged on the outside or inside of the facade, access to the facade cavity is possible in order to check the function of the pressure equalization device and the drying device and to make them accessible for maintenance. It may be necessary to clean the pressure equalization device by blowing it through. Likewise, the pressure equalization device and the drying device can be repaired and replaced.For example, a capillary tube can be replaced, or a cover profile that forms the capillary element together with a groove in the surrounding frame profile. Likewise, if a separate desiccant container is provided, the container can be replaced completely, or the desiccant contained in the drying device can be replaced.

[0095] In summary, there are the following basic variants: Variant 1: Use of a capillary tube The pressure loss of the air flow during pressure equalization is the pressure loss when flowing through the capillary tube. The desiccant interacts directly with the facade cavity and is not passed through by the air duct for pressure equalization. The desiccant can be replaced by access from the outside, preferably from the room side. Optionally, further measures can be taken to increase the vapor tightness of the facade element. Variant 2: Use of a capillary tube The desiccant interacts directly with the capillary tube and is passed through by the air duct for pressure equalization. The total pressure loss of the air flow during pressure equalization is the sum of the pressure loss when flowing through the capillary tube and the pressure loss when flowing through the desiccant. The desiccant can be replaced by access from the outside, preferably from the room side.Optionally, further measures are taken to increase the vapor tightness of the facade element. Variant 3: No capillary tube is provided. Provision of an air duct device that runs through the desiccant. The total pressure loss of the air flow during pressure equalization is the sum of the pressure loss when flowing through the air duct device and the pressure loss when flowing through the desiccant. The desiccant can be replaced via access from the outside, preferably from the room side. Optionally, further measures are taken to increase the vapor tightness of the facade element. Variant 4: No capillary tube is provided. Pressure equalization takes place via an air duct device without flowing through the desiccant. The total pressure loss of the air flow during pressure equalization is the pressure loss when flowing through the air duct device. The desiccant is in air exchange with the cavity in the facade.The desiccant is replaceable through access from the outside, preferably from the room side. Optional additional measures can be taken to increase the vapor tightness of the facade element.

[0096] Which of the variants is preferred depends on the specification of a desired replacement interval for the desiccant, which can be estimated from the climatic conditions at the destination, the volume of desiccant, the water absorption capacity of the desiccant and the design features of the facade element. Short description of the drawings

[0097] The following figures describe the invention purely by way of example using various embodiments. They show: Fig. 1 shows a vertical section through the basic structure of a facade element according to a first variant; Fig. 2 shows a vertical section through the basic structure of a facade element according to a second variant; Fig. 3 shows a vertical section through a facade element according to a first embodiment of the invention; Fig. 4 shows a vertical section through a facade element according to a second embodiment of the invention; Fig. 5 shows a vertical section through a facade element according to a third embodiment of the invention; Fig. 6 shows a vertical section through a facade element according to a fourth embodiment of the invention; Fig. 7 shows a vertical section through a facade element according to a fifth embodiment of the invention; Fig. 8 shows a vertical section through a facade element according to a sixth embodiment of the invention; Fig. 9 shows a vertical section through a facade element according to a seventh embodiment of the invention; Fig.10 shows a vertical section through a facade element according to an eighth embodiment of the invention; Fig. 11 shows a vertical section through a facade element according to a ninth embodiment of the invention; Fig. 12 shows an embodiment of a pressure compensation device according to an embodiment of the invention; Fig. 13 shows an embodiment of a pressure compensation device according to a further embodiment of the invention; Fig. 14 shows a first embodiment of a pressure compensation device with a short capillary tube; Fig. 15 shows a further embodiment with an embodiment of a pressure compensation device in direct interaction with a drying device; Fig. 16 shows a further embodiment with an embodiment of a pressure compensation device with a long capillary tube in direct interaction with a drying device;17 a vertical section through a facade element according to a twelfth embodiment of the invention, which is a variant of the embodiment according to . Fig. 16 with a long capillary tube; Fig. 18 shows a vertical section through a facade element according to a 13th embodiment of the invention, which is a variant of the embodiment according to Fig. 16 with a long capillary tube; Fig. 19 shows a vertical section through a facade element according to a 14th embodiment of the invention, which is a variant of the embodiment according to Fig. 16 with a long capillary tube; Fig. 20 shows a vertical section through a facade element according to a 15th embodiment of the invention, which is a variant of the embodiment according to Fig. 16 with a long capillary tube; Fig. 21 shows a vertical section through a facade element according to a 16th embodiment of the invention, which is a variant of the embodiment according to Fig. 16with a long capillary tube; Fig. 22 shows a vertical section through a facade element according to a 17th embodiment of the invention, which is a variant of the embodiment according to Fig. 16 with a long capillary tube; Fig. 23 shows a second embodiment of a pressure equalization device with a short capillary tube; Fig. 24 shows a third embodiment of a pressure equalization device with a short capillary tube; Fig. 25 shows a fourth embodiment of a pressure equalization device with a short capillary tube; Fig. 26 shows a vertical section through a facade element according to an 18th embodiment of the invention; Fig. 27 shows a detailed view of Fig. 26; Fig. 28(a) to Fig. 28(r) show possible arrangements of pressure equalization and drying devices in a facade element according to the invention; Fig. 29 shows a vertical section through the sub-frame profile of a facade element in a section plane parallel to the glass plane of the facade element according to a 19th embodiment of the invention; Fig. 30 shows a vertical section through the sub-frame profile of a facade element in a section plane parallel to the glass plane of the facade element according to a 20th embodiment of the invention; Fig. 31 shows a vertical section through the sub-frame profile of a facade element in a section plane parallel to the glass plane of the facade element according to a 21st embodiment of the invention; Fig. 32 shows a vertical section through the sub-frame profile of a facade element in a section plane parallel to the glass plane of the facade element according to a 22nd embodiment of the invention;33a a vertical section through the sub-frame profile in a section plane parallel to the glass plane of the facade element according to a 23rd embodiment of the invention; Fig. 33b a vertical sectional view in a section plane perpendicular to the glass plane of the 23rd embodiment of the invention; Fig. 34a a vertical section through the sub-frame profile in a section plane parallel to the glass plane of the facade element according to a 24th embodiment of the invention; Fig. 34b a vertical sectional view in a section plane perpendicular to the glass plane of the 24th embodiment of the invention; Fig. 35a a vertical section through the sub-frame profile in a section plane parallel to the glass plane of the facade element according to a 25th embodiment of the invention; Fig. 35b a vertical sectional view in a section plane perpendicular to the glass plane of the 25th embodiment of the invention; Fig. 35c a variant of the embodiment according to. Fig. 35bin a first operating position; Fig. 35a variant of the embodiment according to Fig. 35bin a second operating position; Fig. 36a a vertical section through the subframe profile in a section plane parallel to the glass plane of the facade element according to a 26th embodiment of the invention; Fig. 36b a vertical sectional view in a section plane perpendicular to the glass plane of the 26th embodiment of the invention; Fig. 37a a vertical section through the subframe profile in a section plane parallel to the glass plane of the facade element according to a 27th embodiment of the invention; Fig. 37b a vertical sectional view in a section plane perpendicular to the glass plane of the 27th embodiment of the invention; Fig. 38a a vertical section through the subframe profile in a section plane parallel to the glass plane of the facade element according to a 28th embodiment of the invention; Fig. 38b a vertical sectional view in a section plane perpendicular to the glass plane of the 28th embodiment of the invention; Fig.39a a vertical section through the subframe profile in a section plane parallel to the glass plane of the facade element according to a 29th embodiment of the invention; Fig. 39b a vertical sectional view in a section plane perpendicular to the glass plane of the 29th embodiment of the invention; Fig. 40a a vertical section through the subframe profile in a section plane parallel to the glass plane of the facade element according to a 30th embodiment of the invention; Fig. 40b a vertical sectional view in a section plane perpendicular to the glass plane of the 30th embodiment of the invention; Fig. 41a a vertical section through the subframe profile in a section plane parallel to the glass plane of the facade element according to a 31st embodiment of the invention; Fig. 41b a vertical sectional view in a section plane perpendicular to the glass plane of the 31st embodiment of the invention; Fig.42a a vertical section through the sub-frame profile in a section plane parallel to the glass plane of the facade element according to a 32nd embodiment of the invention; Fig. 42b a vertical sectional view in a section plane perpendicular to the glass plane of the 32nd embodiment of the invention; Fig. 43a a vertical section through the sub-frame profile in a section plane parallel to the glass plane of the facade element according to a 33rd embodiment of the invention; Fig. 43b a vertical sectional view in a section plane perpendicular to the glass plane of the 33rd embodiment of the invention; Fig. 44a a vertical sectional view in a section plane perpendicular to the glass plane of the 34th embodiment of the invention and Fig. 44b a detailed view in a further section of the embodiment according to. Fig. 44a . Ways to implement the invention

[0098] In the following figures, the same components are designated with the same reference numerals. In the following embodiments, only the specific differences and deviations from previous embodiments are explained, while the basic structure of the facade element in the embodiments according to Fig. 1 and 2 is described.

[0099] In all figures, the arrows labeled "DA" indicate the direction of air movement during pressure equalization, and the arrows labeled "TR" indicate the direction of air exchange of dried air from the drying device into the façade cavity during drying. If these directions coincide, the designation "DA + TR" is also used. The arrows "AT" indicate the direction in which the desiccant can be replaced or, if a separate desiccant container is used, the direction in which the desiccant container can be replaced.

[0100] In Fig. 1 A vertical section through a facade element 1 without a pressure equalization device and drying device is shown. On the outside of the facade, an outer glass element 2 is arranged, which in the present exemplary embodiment is sealed on the outside to form a glazing bead 10 via outer sealing strips 33. Towards the inside and in particular in the direction of the interior space 3 of the facade, the outer glass element 2 is held by the inner seal 25. The inner seal 25 is inserted into a sub-frame profile 7. A seal 27 is located between the sub-frame profile 7 and the end faces of the outer glass element 2. An outer expansion joint seal 30 is also inserted into the sub-frame profile 7. This seal, together with the inner expansion joint seal 28 arranged on the inside of the facade and the middle expansion joint seal 29, seals the expansion joint 78 between the vertically adjacent glass elements.

[0101] The subframe profile 7 is screwed to the main frame profile 6 of the surrounding frame profile 11 using connecting screws 9. A seal 8 is provided between the main frame profile 6 and the subframe profile 7, which seal is preferably made of thermoplastic butyl or another suitable material with high vapor impermeability. In the illustrated embodiment, the main frame profile 6 is formed as a composite profile with main frame profile sections 6a and 6b, which are thermally decoupled via insulating webs 24 made of plastic with increased vapor impermeability. A sun protection device 5, which is shown schematically in the present exemplary embodiment, is arranged in the facade cavity 3.

[0102] On the inside of the facade, an inner glass element 4 is provided as a multiple-pane insulating glass unit. It is held by an inner seal 31 toward the stop and toward the facade cavity 3 by a seal 32, which is held in the facade cavity by a glazing bead 20. The provision of an inner seal increases vapor tightness compared to a seal. Reduced vapor tightness is disadvantageous because it leads to a more rapid depletion of the desiccant container and thus shortens the desiccant replacement intervals.

[0103] Fig. 1 thus represents a first variant of the basic structure of the facade element, which, as in the embodiments starting from Fig. 3 shown, is provided with a pressure equalization device and drying device.

[0104] Fig. 2 represents a variant of the embodiment according to Fig. 1in which the facade element does not have a glazing bead 10 arranged on the outside of the facade and accordingly also no external sealing strips 33, which are also omitted with the omission of the outer glazing bead 10. The outer glass pane 2 is attached to the subframe profile 7 by means of the seal 26. Otherwise, the structure corresponds to Fig. 2 the one after Fig. 1 , so that the explanation regarding the Fig. 1 can be referred to.

[0105] In the Fig. 3 is based on the Fig. 1 The basic construction of the facade element 1 already shown shows a first alternative design of a pressure compensation device and drying device. In the embodiment according to Fig. 3Both the pressure equalization device and the drying device are arranged in the sub-frame profile 7. For this purpose, desiccant 14 is located in a hollow chamber 80 of the sub-frame profile 7. The desiccant 14 can be exchanged in the vertical direction in the direction of arrow AT between the expansion joint 78 and the hollow chamber 80 in the sub-frame profile 7 filled with desiccant 14. In the direction of the facade gap 3, both pressure equalization and, together with the pressure equalization, the transport of moisture-laden air from the facade gap 3 into the hollow chamber 80 filled with desiccant 14 can take place, where the water vapor is adsorbed on suitable adsorbents, such as zeolites, and in this way the internal atmosphere in the facade gap 3 is kept at a stable, low level of humidity.

[0106] In Fig. 3Additionally indicated with reference number 56 are measures for providing a vapour barrier in the area of ​​the insulation bars 24, for example in the form of a selection of suitable materials for the insulation bars.

[0107] The embodiment according to Fig. 4 differs from that according to Fig. 3in that the hollow chamber 80 provided in the sub-frame profile 7, in conjunction with a long or short capillary tube connected to the outside atmosphere and the façade cavity, serves to equalize pressure, as shown by the arrows DA. The main frame profile 6 has a hollow chamber 13 filled with desiccant 14. In addition, openings 15 are provided between the hollow chamber 13 in the main frame profile 6 and the façade cavity 3, which allow air exchange so that moisture-laden air can penetrate into the hollow chamber 13, whereupon the desiccant 14 located therein adsorbs the moisture. The exchange of moisture-laden desiccant takes place in the direction of the arrow AT towards the inside of the façade. In contrast to the embodiment according to Fig. 3 , in which the pressure compensation device and drying device in the subframe profile 7 are in direct interaction with each other, in the embodiment according to Fig. 4 no direct interaction between the pressure compensation device and the drying device, since the pressure compensation device is arranged in the sub-frame profile 7, while the drying device is located in the main frame profile 6.

[0108] The Fig. 4 The direction "AT" shown for the exchange of water vapor-laden desiccant with a freshly regenerated desiccant is only given in general terms. A possible technical implementation of the exchange is based on the Fig. 26 and Fig. 27 be explained.

[0109] The embodiment according to Fig. 5 is similar to that according to Fig. 4, but differs in that between the hollow chamber 80 in the sub-frame profile 7, which is in air exchange with the expansion joint 78 for the purpose of pressure equalization (arrow direction DA), there is an air-conducting connection via a pressure equalization sub-system 17 with the hollow chamber 13 in the main frame profile 6. The pressure equalization to the facade cavity 3 thus takes place from the expansion joint 78 into the hollow chamber 80 of the sub-frame profile 7 and through the pressure equalization sub-system 17 into the hollow chamber 13 filled with desiccant 14 and through the openings 15, whereas in the embodiment according to Fig. 4 the hollow chamber 80 in the subframe profile 7 has an air-conducting connection to the expansion joint 78 as well as to the facade cavity 3, which enables pressure equalization.

[0110] Thus, in the embodiment according to Fig. 5the pressure compensation device and the drying device interact directly with each other because the pressure compensation device is arranged in the sub-frame profile 7 and between the sub-frame profile 7 and the main frame profile 6, and the drying device is arranged in the main frame profile 6.

[0111] Another variant is in Fig. 6 Here, both the pressure equalization device and the drying device are integrated in the hollow chamber 13 in the main frame profile 6. This solution is therefore similar to that according to Fig. 3 , as far as the direct interaction of the pressure compensation device with the drying device is concerned. In contrast to the embodiment according to Fig. 3 However, the combined system is located in a cavity 13 in the main frame profile 6, while in the embodiment according to Fig. 3The desiccant 14 is located in a cavity 80 in the subframe profile 7. For this purpose, pressure equalization openings 18 are provided between the hollow chamber 13 in the main frame profile 6 and the expansion joint 78, as well as openings 15 between the hollow chamber 13 and the façade gap 3, allowing pressure equalization between the façade gap 3 and the expansion joint area. The air flow between the expansion joint and the drying device occurs through a foam block 22 whose core is open-cell.

[0112] In the design according to the Fig. 3 to 6 the hollow chamber 13 filled with desiccant is arranged in such a way that it is not located in the transparent viewing area of ​​the facade element 1 and thus cannot be perceived as disturbing.

[0113] Even in the embodiment according to Fig. 7The drying device is located in the area of ​​the main frame profile 6. In contrast to the previous embodiments, however, the drying device comprises a separate desiccant container 19, which can be fastened to the main frame profile 6 in the façade gap 3. The desiccant container 19 is replaced by completely removing it in the direction of arrow AT and reattaching it to the main frame profile 6 with regenerated desiccant. The desiccant container 19 has openings 15, which connect the inner cavity 69 of the desiccant container 19, filled with desiccant 14, to the façade gap 3, so that air exchange can take place and water vapor in the façade gap 3 can be bound by the desiccant 14 located in the desiccant container 19. The pressure compensation device in the embodiment according to Fig. 7 in the same way as in the embodiment according to Fig. 4designed. Pressure equalization is achieved by having a cavity 80 of the subframe profile 7 in air communication with both the expansion joint 78 and the façade gap 3. Thus, the pressure equalization device in the subframe profile 7 and the drying device in the form of a replaceable desiccant container 19 are provided without direct interaction with each other. The desiccant container 19 has a shape that is not disruptive when viewed from the inside of the façade outwards or from the outside of the façade inwards.

[0114] The embodiment according to Fig. 8 combines the basic ideas of the embodiments according to Fig. 6 and 7 As with the design according to Fig. 7 A separate desiccant container 19 is provided, which, however, in contrast to the embodiment according to Fig. 7not only serves as a drying device, but also has a pressure equalization device integrated into it. For this purpose, in addition to the Fig. 7 In addition to the openings 15 already described, which create an air connection between the interior of the desiccant container 19 and the facade gap 3, additional pressure equalization openings 18 are provided, which also in the case of the Fig. 8The illustrated interposition of a cavity 13 in the main frame profile 6 creates a flow connection between the expansion joint 78 and the inner cavity 69 of the desiccant container 19 filled with desiccant 14, so that pressure equalization can take place between the expansion joint 78 and the façade gap 3 via the pressure equalization openings 18, the inner cavity 69 of the desiccant container 19 and the openings 15. Both the pressure equalization device in the main frame profile 6 and in the desiccant container 19 as well as the drying device as an exchangeable container in the façade gap 3 are thus in direct interaction with each other. The pressure equalization device and the drying device are arranged and dimensioned such that they do not extend into the transparent area 12 of the façade element. The transparent area extends in the plane of the drawing of the Fig. 8from the inner seal 32 of the inner glazing 4 upwards, because only in this area, when viewed perpendicular to the main plane of the outer glazing 2 through the facade element, both the outer glazing 2 and the inner glazing 4 are transparent, provided the sun protection device 5 is not in the operating position.

[0115] The embodiment according to Fig. 9 essentially corresponds to that according to Fig. 3. Films are applied to the insulating webs 24 for thermal separation of the partial profiles 6a and 6b of the main frame profile 6. Reference number 23a denotes a film made of very thin stainless steel with a thickness of no more than 0.050 mm, or of metal-coated plastic film, or of butyl film on the insulating web on a surface facing the expansion joint. Reference number 23b denotes a film as described above, but on the insulating web 24 on a side facing away from the expansion joint. These measures serve to further increase the vapor-tightness of the insulating webs and thus reduce the diffusion of water vapor into the facade cavity 3.

[0116] In the embodiment according to Fig. 10An opaque element is shown, which is provided in the form of a parapet panel 58 in the plane of the inner glass element 4 and an opaque coating 60 in the plane commonly referred to as position 2 on the outer glass pane. In this embodiment, it is advisable to arrange a separately provided desiccant container 19 in the opaque area. In the embodiment according to Fig. 10The desiccant container 19 is located as a replaceable container in the area of ​​the parapet in front of the parapet panel 58. The desiccant container 19 also represents part of the pressure equalization device with openings 15 in the facade gap 3 surrounding the desiccant container 19. Between the two vertically adjacent facade elements there is an air guide element 21 which has an internal cavity and connects the internal cavity 69 of the desiccant container in the parapet panel 58 with the facade gap 3 of the adjacent panel. For this purpose, the air guide element, which can be a pipe or hose, for example, is inserted through insertion openings 18a in the main profile 6 and fixed in a sealing manner in the insertion openings 18a on the outside of the insertion element 21. In this way, pressure equalization in the facade gap 3 of the adjacent facade element is achieved and incoming air is dehumidified at the same time.

[0117] The embodiment according to Fig. 11 leans closely against the one after Fig. 10 In contrast to the embodiment according to Fig. 10 However, in the opaque area, an interior space in the area of ​​the frame of the main frame profile 6 is completely filled with insulating material 62. For this reason, the desiccant container 19 also occupies the entire depth of the main frame profile 6 and the openings 15 are provided on the front side in the desiccant container 19 in order to be able to establish pressure equalization there via the facade gap 3, which is not filled with insulating material, in the area of ​​the sub-frame profile 7. Via the air guide element 21, as in the embodiment according to Fig. 10 , the pressure equalization to the facade gap 3 of the vertically adjacent facade element and the drying of the incoming air are carried out.

[0118] The above examples clearly demonstrate that there are two basic concepts regarding the pressure equalization device. Firstly, a direct air connection can be established with the façade cavity, so that there is no direct interaction with the drying device. Secondly, a connection to the façade cavity can also be established above and through the drying device, so that there is a direct interaction between the pressure equalization device and the drying device.

[0119] The embodiment according to Fig. 12shows in detail the pressure equalization device that is integrated into the sub-frame profile 7. For this purpose, a long capillary tube 35 is clipped into the sub-frame profile 7. The long capillary tube can preferably be made of metal or plastic. Thermoplastics or elastomers can be used as plastics. A filter element or a membrane can be arranged at the inlet of the capillary tube (not shown in the section), which is in air-conducting connection with the outside atmosphere. In the same way, alternatively or additionally, a filter or a membrane can be provided at the outlet of the capillary tube (not shown in the section). The outlet of the capillary tube is in air-conducting connection with the hollow chamber 80 in the sub-frame profile 7. The hollow chamber 80 in the sub-frame profile 7 is provided with a filter 36 in a pressure equalization opening to the facade cavity 3.In this way, pressure equalization between the facade cavity 3 and the outside atmosphere can be achieved via the cavity 80 and the capillary tube 35 in the direction of arrow DA, via the cavity 80, via an air-conducting connection between the cavity 80 and an outlet opening of the long capillary tube 35, and via the air-conducting connection between the inlet opening of the long capillary tube 35 and the outside atmosphere. The design according to . Fig. 12 is an example of those designs in which there is no direct interaction between the pressure compensation device and the drying device.

[0120] The embodiment according to Fig. 19 is similar to that according to Fig. 12 , but instead of the long capillary tube used Fig. 12a plastic profile 66 made of a thermoplastic or elastomer. For this purpose, a groove 53 is formed in the area of ​​the hollow chamber 80 in the subframe profile 7, and the plastic profile 66 is inserted into the groove 53 to seal the groove 53 at a distance from the groove. A groove 51 with a rectangular cross-section is provided in the plastic profile 66 made of a thermoplastic or elastomer, which represents the capillary element. An opening 68 is also located in the groove 53, which connects the cavity 80 to the groove 51. The groove is connected to the outside atmosphere via a gap in the plastic profile 66. The desired pressure equalization takes place via the plastic profile 66, the hollow chamber 80, and, in the direction of arrow DA, the filter 36 in the pressure equalization opening 34 of the hollow chamber 80 of the subframe profile 7.

[0121] The embodiment according to Fig. 20 differs from that according to Fig. 19merely by providing a distance that forms a gap 55 between the groove 53 in the subframe profile 7 and the plastic profile 66 inserted into the groove 53. The plastic profile 66 for sealing the groove 53 consists of a thermoplastic or elastomer and must be both sufficiently adaptable and sufficiently vapor-tight, which must be taken into account when selecting a suitable plastic profile. The gap 55 forms the capillary element and is connected to the hollow chamber in the subframe profile 7 via the opening 68. As already in the embodiment according to Fig. 19 also exists in the embodiment according to Fig. 20 no direct interaction between the pressure equalization device and the drying device.

[0122] When designing according to Fig. 21 is in contrast to that according to Fig. 19The hollow chamber 80 in the subframe profile 7 is filled with desiccant 14. Thus, there is a direct interaction between the pressure compensation device and the drying device. The capillary element is again, as in the embodiment according to Fig. 19 , formed by a groove 53 in the subframe profile 7 and a gap 51 in the plastic profile 66, which forms a long capillary element. The cross-section of the capillary element 51 is rectangular. A filter 36 is inserted into the pressure equalization opening to the facade cavity 3.

[0123] The Fig. 22 represents a variant of the design according to Fig. 20, in which the hollow chamber 80 in the sub-frame profile 7 is also additionally filled with desiccant 14. The pressure compensation device thus again comprises a long capillary groove, which is formed by the gap 55 between the plastic profile 66 made of a thermoplastic or elastomer and the groove 53, as well as the filter 36 between the hollow chamber 80 and the facade gap 3. By filling the hollow chamber 80 with desiccant 14, however, in contrast to the embodiment according to Fig. 20 a direct interaction between the pressure equalization device and the drying device.

[0124] In the embodiment according to Fig. 17There is a pressure equalization opening 37 with a filter 36 in the subframe profile 7, which connects the hollow chamber 80 in the subframe profile 7 with the outside atmosphere. In addition, a groove 38 is provided in the main frame profile 6 as part of a long capillary tube. In this groove there is a plastic profile 47 made of a thermoplastic or elastomer, which serves to seal the groove 38 and is provided with a gap 48 as part of the capillary tube cross-section. Thus, the pressure equalization device comprises elements in both the subframe profile 7 and the main frame profile 6. A capillary groove is formed in the main frame profile 6, which comprises a groove 38 and a gap 48 in the plastic profile 47. The cavity 13 in the main frame profile 6 adjacent to the groove 38 in the main frame profile 6 is filled with desiccant 14. An opening (in the sectional plane of the Fig. 17not shown) connects the long capillary tube with the hollow chamber filled with desiccant 14 in the main frame profile 6. Therefore, there is a direct interaction between the pressure equalization device and the drying device.

[0125] The design according to Fig. 18 differs from that according to Fig. 17in that a differently shaped, elongated plastic profile 49 made of a thermoplastic or elastomer is inserted into the groove 38 in the main frame profile 6, which also serves to seal the groove 38, but ends at a distance from the groove base, so that a gap 50 is present between the groove 38 in the main frame profile 6 and the plastic profile 49. The pressure compensation device is thus again formed both in the subframe profile 7 and the main frame profile 6. A capillary groove is provided in the main frame profile 6, which is formed by the gap 50 between the groove 38 and the plastic profile 49. In addition, the pressure compensation device interacts directly with the drying device, since the cavity 13 in the main frame profile 6 adjacent to the groove 38 is filled with desiccant 14 and there is an opening in the groove 38 into the cavity filled with desiccant.A filter 36 in the subframe profile 7 prevents the penetration of dirt.

[0126] The embodiment according to Fig. 13 is similar to that according to Fig. 18 However, the sealing plastic profile 39 made of a thermoplastic or elastomer inserted into the groove 38 in the main frame profile 6 is differently shaped. Within the groove 38, a gap 50 is provided, which forms a cavity and takes on the function of a long capillary tube. The cross-sectional dimensions of the capillary tube can be adapted by suitable selection of the dimensions of the plastic profile 39. Desiccant 14 is filled in the hollow chamber 13 in the main frame profile 6 adjacent to the groove 38. The groove 38 has a pressure equalization opening 72 to the hollow chamber 13 in the main frame profile 6 filled with desiccant 14. A filter 70 can optionally be located in the pressure equalization opening 72. In contrast to the embodiments according to the Figures 18 and 19is in the design according to Fig. 13 the cross-sectional area of ​​the gap 50 is larger. Accordingly, a very long capillary tube must be selected for this embodiment. The longer the capillary tube, the better its function as a moisture barrier. A filter 36 in the subframe profile 7 prevents the penetration of dirt.

[0127] In Fig. 14 a pressure compensation device with direct interaction with a drying device is shown, which is the general representation according to Fig. 8further specified. A separately provided desiccant container 19 is provided, which can be attached to and removed from the main frame profile 6 in the direction of arrow AT, for example via a screw connection. A pressure equalization opening 42 is provided in the main frame profile 6 and a correspondingly arranged opening in the desiccant container 19, which can advantageously be provided with a filter 36 that represents a desiccant particle barrier. In addition, a maintenance opening 43 is provided in the main frame profile 6, through which the short capillary tube 41 with membrane 45, which is located in a pressure equalization opening 18 in the main frame profile 6, can be replaced. The membrane acts as a filter and moisture barrier.There is an air-conducting pressure equalization path in the direction of arrow DA from the outside atmosphere into the cavity 69 of the desiccant container 19 filled with desiccant 14 and from there through corresponding openings 15 into the facade gap 3. The air exchange between the inner cavity 69 of the desiccant container 19 and the facade gap 3 also takes place through the latter openings 15 in order to regulate the moisture content of the air in the facade gap 3.

[0128] Fig. 15 shows a design similar to that of Fig. 14, but using a long capillary tube. For this purpose, a removable and therefore replaceable desiccant container 19 filled with desiccant 14 can be attached to the main frame profile 6. The pressure equalization device comprises a long capillary tube 35, which is inserted into a correspondingly dimensioned receiving groove in the desiccant container on the side of the desiccant container 19 facing the main frame profile 6. The long capillary tube is made of metal or of a thermoplastic or elastomeric material. The outlet end of the long capillary tube 35 protrudes via a Fig. 15 The opening is not visible and is in air-conducting connection with the inner cavity 69 of the desiccant container 19. Thus, there is a direct interaction between the pressure compensation device and the drying device. The outlet end of the long capillary tube 35 is connected to the drying device via a Fig. 15invisible opening in air-conducting connection with the inner cavity 69 of the desiccant container 19. An inlet opening of the Fig. 15 The long capillary tube 35, shown only in section, is in air-conducting connection with a connecting piece 44, which also has an internal flow channel for air and whose end facing away from the long capillary tube 35 is in air-conducting connection with a pressure equalization opening 18 in the main frame profile 6, which establishes the flow connection to the expansion joint 78. A filter 36 is provided in the pressure equalization opening 18 in the main frame profile 6.

[0129] The replacement of the desiccant container 19 in the direction of arrow AT is carried out as in the embodiments according to Fig. 8 and 14 , and the air exchange between the facade gap 3 and the cavity 69 of the desiccant container 19 filled with desiccant 14 also takes place as in connection with the embodiment according to Fig. 14 was described.

[0130] In a variation of Fig. 15 shows the Fig. 16 a different design of a long capillary tube, which is composed of two sections of an elongated cavity 46, a groove-shaped recess 74 in the wall of the desiccant container 19 and the wall of the main frame profile 6 with an opening in which the connecting piece 44 is arranged. The outlet end of the long capillary tube 46 protrudes via a Fig. 16 invisible opening in air-conducting connection with the inner cavity 69 of the desiccant container 19. The inlet opening of the Fig. 16The long capillary tube 46, shown only in section, is in air-conducting connection with the connecting piece 44, which also has an internal flow channel for air and whose end facing away from the long capillary tube 46 is in air-conducting connection with a pressure equalization opening 18 in the main frame profile 6, which establishes the flow connection to the expansion joint 78. A filter 36 is provided in the pressure equalization opening 18 in the main frame profile 6. Otherwise, the embodiment according to Fig. 16 those after Fig. 14 and 15 .

[0131] In the Fig. 23A further embodiment is shown using a short capillary tube 41 with a membrane 45, which is in air-conducting connection with a pressure equalization opening 37 in the sub-frame profile 7. For pressure equalization, air passes from the expansion joint 78 into the hollow chamber 80 in the sub-frame profile 7 via the short capillary tube and from there via the pressure equalization opening 34 into the facade gap 3. The drying device comprises desiccant 14 in a hollow chamber 13 of the main frame profile 6. The hollow chamber is in air exchange with the facade gap 3. Thus, there is no direct interaction between the pressure equalization device and the drying device.

[0132] The embodiment according to Fig. 24 is a variation of the one according to Fig. 23 There is a direct interaction between the pressure compensation device and the drying device, because in contrast to the embodiment according to Fig. 23There is no direct air exchange between the hollow chamber 80 in the sub-frame profile 7 and the facade cavity 3, because the hollow chamber 80 is in air communication with the hollow chamber 13 of the main frame profile 6, which is filled with desiccant. For this purpose, there are aligned openings in the hollow chamber 80 and the hollow chamber 13, through which, as can be seen from the Fig. 5 As described, the pressure equalization between the outside atmosphere and the space between the facade takes place with the drying device interposed.

[0133] The embodiment according to Fig. 25 used as well as the designs according to Fig. 23 and 24a short capillary tube 41 with a membrane 45, whose inlet opening is in air-conducting communication with a pressure equalization opening 37 in the subframe profile 7. There is a direct interaction between the pressure equalization device and the drying device because the hollow chamber 80 in the subframe profile 7 is filled with desiccant 14. Furthermore, a pressure equalization opening 34 is provided in the hollow chamber 80, which is in air-conducting communication with the facade cavity 3. A filter element 36 is located in the pressure equalization opening 34.

[0134] The embodiment according to Fig. 26 shows how the embodiment according to Fig. 10 , an opaque panel 58 in the parapet area, which is provided instead of the inner glazing element. The designs of the pressure equalization device and the drying device, however, correspond to those in Fig. 18 are shown in a detailed view and have already been explained.

[0135] Panel 58 is thermally insulated and has an outer cover shell 59, which is typically made of metal. The cover shell is preferably dark toward the façade cavity, and particularly preferably dark and matte.

[0136] An inner cover shell 61 is provided on the room side. An insulating material 62 is located between the cover shells 59 and 61. The insulating panel is preferably open-cell and made of mineral wool, organic foam, aerogel, or a vacuum panel. The panel 58 is held to the facade cavity 3 by a strip 20 with a sealing strip 57 interposed therebetween, while an inner seal 31 is provided on the room side. An optional sun protection device 5' can also be provided in the area of ​​the panel 58, particularly if the outer glazing element 2 at position 2 is not provided with an opaque coating 60.

[0137] The exchange of desiccant 14 as well as the injection of fresh, regenerated desiccant is carried out with the aid of an exchange device 16, which extends through a hollow chamber 67 of the main frame profile 6 and whose inner cavity 65 connects the room side of the facade element 1 with the hollow chamber 13 in the main frame profile 6, in which the desiccant 14 is located. In order to prevent the penetration of water vapor from the room side into the cavity 13 filled with desiccant, as shown in the detailed view in Fig. 27As shown, a room-side sealing element 64 is provided which seals the inner cavity 65 of the exchange device at its room-side end. In addition, in the area of ​​the opening between the cavity 13 filled with desiccant 14 and the hollow chamber 67 of the main frame profile 6, a sealing part 63 is provided which serves to prevent the penetration of water vapor from the hollow chamber 67 of the main frame profile 6 into the cavity 13 filled with desiccant. If the desiccant 14 is to be replaced, the sealing element 64 is removed and the desiccant 14 is sucked out through the inner cavity of the exchange device 16 towards the room side in the direction of arrow A. Fresh desiccant can then be blown in the direction of arrow B through the inner cavity 65 of the exchange device 16 into the hollow chamber 13 and the sealing element 64 can then be replaced.In this way, the desiccant 14 can be easily replaced from the room side.

[0138] In Fig. 28 Various possible arrangements of the pressure equalization and drying device are schematically shown in the schematic representations 28(a) to 28(r). "F" represents the window area, and "B" denotes the optionally provided, opaque area, which is preferably located in the parapet area. Dashed lines indicate a long capillary tube interacting with a drying device, while in the plane of the drawing the Fig. 28 horizontal dash-dotted lines indicate a long capillary tube without interaction with a drying device. The lines in the plane of the drawing of the Fig. 28 The horizontal lines correspond to a horizontal direction when the facade element is installed as intended. Fig. 28(a) to (r)The vertical dash-dotted lines shown correspond to a pressure equalization device with a membrane and a short capillary tube. Finally, a distinction must be made regarding the arrangement of the pressure equalization openings. Straight, solid lines indicate an outward or inward pressure equalization opening, while solid lines bent at right angles indicate an inward pressure equalization.

[0139] As from the Fig. 28 As can be seen, there are 18 practical options for arranging pressure equalization and drying devices. The arrangement of the pressure equalization and drying devices depends on the choice of pressure equalization system, in particular the choice of a short or long capillary tube, as well as on the building's specific conditions. Short capillary tubes are preferably installed in vertical frame sections.

[0140] In the embodiments without the interaction of the volume flow of air during pressure equalization with the desiccant, as exemplified in the embodiments according to the Figures 4 and 7 As shown in the diagram, the provision of a capillary tube can be omitted if the air flow is designed in such a way that a sufficient service life can be achieved until the desiccant is required to be replaced. Various designs are possible, which are described in the Figures 29 to 32 are shown.

[0141] When designing according to the vertical section in Fig. 29 The air flow for pressure equalization takes place entirely in the sub-frame profile 7. For this purpose, a first pressure equalization opening 82 and a second pressure equalization opening 84 are provided, which are provided in the sub-frame profile 7 and in the example according to Fig. 29as far as possible vertically spaced from each other and arranged in the immediate vicinity of the corner angles 86 in the mitred corners of the sub-frame profile 7. The first pressure equalization opening 82 is arranged at the lowest point of the vertical part of the sub-frame profile, is connected to the outside atmosphere and runs diagonally downwards along a slope at the corner angle, so that dust penetrating through the first pressure equalization opening 82 into the inner cavity of the sub-frame profile 7 can settle downwards and escape from the sub-frame profile. The second pressure equalization opening 84 is provided at the highest point of the, for example, 4 meter vertical part of the sub-frame profile 7 and connects the facade gap 3 with the inner cavity of the sub-frame profile 7. Fig. 29The straight air duct shown can already extend the service life of the desiccant compared to the case of direct air ingress from the outside atmosphere into the facade cavity, which is defined by the provision of two aligned holes through the subframe profile.

[0142] Alternatively to the design according to Fig. 29 The air flow during pressure equalization can be carried out in a front cover 88, which in the vertical section through the subframe profile according to Fig. 30is fastened to the sub-frame profile 7, preferably clipped on or screwed to the sub-frame profile 7. The front cover has an inner cavity 90 and has a vertical extension which essentially corresponds to the height of the vertical part of the sub-frame profile 7. The first pressure equalization opening 82 is provided at the bottom end of the front cover 88 at the lowest point of the sub-frame profile and points in a vertical direction, so that dust penetrating into the inner cavity of the front cover 88 can automatically fall back down out of the first pressure equalization opening 82 under the influence of gravity. At the upper end of the front cover, at the upper end of the vertical part of the sub-frame profile, an opening towards the sub-frame profile 7 is provided.The air flow during pressure equalization flows between the upper end of the front cover 88 and a sleeve 92, which extends through the subframe profile 7 and leads into the facade cavity 3. The one shown in . Fig. 30 The largely straight air flow shown with only a single 90° deflection at the top of the air flow can extend the service life of the desiccant compared to the case of direct air entry from the outside atmosphere into the facade cavity.

[0143] The Fig. 31 converts the flow pattern according to Fig. 30in that a flow connection exists between the inner cavity 90 of the inner cover 88 and the inner cavity 96 of the subframe profile 7 via an air exchange opening 94 in the subframe profile 7 at the upper end of the attached cover 88. The second pressure equalization opening 84 connects the facade gap 3 and the inner cavity 96 of the subframe profile 7 and is provided approximately at the height of the first pressure equalization opening 82, so that upon pressure equalization, the air flow is deflected twice and covers a distance that essentially corresponds to twice the height of the vertical part of the subframe profile 7. This flow guidance results in a double deflection of the air flow, between which the air flow runs essentially in a straight line.

[0144] The variant according to Fig. 32 corresponds to the design according to Fig. 29, to which reference is made, is modified in that an insertion element 98 is arranged in the inner cavity 96 of the sub-frame profile 7, said insertion element comprising a first wall 102 and a second wall 104, to each of which at least one transverse bulkhead 106 is attached, the mutual arrangement of which determines the air guidance in contrast to the straight-line air guidance according to the embodiment according to Fig. 29 deflected several times and forces a winding flow path. The vertically arranged transverse bulkheads 106 have a downward inclination towards the side of the free flow cross-section and therefore act as additional dust brakes. Fig. 32 With the air flow system shown, with several deflections of the air flow, the service life of the desiccant can be further extended compared to the case of direct air entry from the outside atmosphere into the facade cavity.

[0145] According to a further embodiment of the invention (not shown), the Figuren 31 and 32 The measures explained above can be combined by providing an upstream cover and, in addition, alternately arranged transverse bulkheads are provided either in the inner cavity of the sub-frame profile or in the inner cavity of the upstream cover, which represent additional deflections of the air flow. However, it is preferred in this case to provide the transverse bulkheads in the upstream cover, since they can fulfill the additional function of a dust brake and prevent or at least reduce the penetration of dust into the sub-frame profile. When combining the Figuren 31 and 32 The measures explained can extend the service life of the desiccant even further compared to the case of direct air ingress from the outside atmosphere into the cavity between the facade.

[0146] In all designs with an upstream cover, this can additionally consist of a plastic material that can absorb moisture and thus serves as a moisture buffer, which dehumidifies incoming air within the scope of its moisture absorption capacity and releases the absorbed moisture back into the dried air flowing out of the façade cavity.

[0147] The one based on the Fig. 7 , 8 and 29 bis 32 A common feature of the illustrated embodiments is that the pressure equalization between the outside atmosphere and the façade cavity occurs separately from the air exchange between the façade cavity and a desiccant. Furthermore, these embodiments have in common that a dust filter can be additionally provided in the area of ​​the first pressure equalization opening. By omitting a capillary tube, the design of the air duct alone can significantly increase the service life of the desiccant until the moisture-laden desiccant needs to be replaced.

[0148] To further increase the service life of the desiccant, the air flow should be directed through the desiccant during pressure equalization.

[0149] In the Figuren 33a and 33b A first possible design is shown, where Fig. 33a represents a vertical section through the subframe profile in a cutting plane parallel to the glass plane of the facade element and Fig. 33b shows a vertical sectional view in a cutting plane perpendicular to the glass plane.

[0150] The design of the subframe profile according to Fig. 33a is similar to that according to Fig. 29 and differs only in that instead of the second pressure equalization opening between the inner cavity 96 of the subframe profile 7 and the facade gap 7, an opening 108 to the desiccant chamber is provided. The opening 108 is preferably a bore. For all other design features, please refer to the explanations for Fig. 29 be referred to.

[0151] The Fig. 33b The dotted lines schematically indicate the flow pattern of the air stream during pressure equalization. This representation is simplified, however, because gas flow through a bed of solid particles such as desiccant pellets is not linear, but rather follows a winding path with numerous branches. However, the dotted lines are intended to indicate which measures can be advantageously taken to load the desiccant with moisture as evenly as possible.

[0152] The following will explain the situation when negative pressure prevails in the cavity between the facade and air flows from the outside atmosphere into the cavity. However, the principles explained are equally applicable to air flow in the opposite direction.

[0153] After flowing into an inner cavity 110 of the main frame profile 6, which is filled with desiccant, the air flow is drawn to the openings 112a, 112b, and 112c, which connect the inner cavity 110 of the main frame profile 6 to the facade cavity 3. The driving force for the air flow is the air pressure at the openings 112a, 112b, and 112c, which is lower than that of the air flow upon entering the desiccant bed 98 through the opening 108.

[0154] The provision of three openings results in the air flow to all openings, although the pressure loss through the desiccant bed 98 is essentially proportional to the distance between the opening 108 and the respective opening 112a, 112b, 112c. To counteract the effect that the air flow prefers the path with the lowest flow resistance, the openings 112a, 112b, 112c have different opening diameters. The opening diameter d1 of the opening 112a closest to the opening 108 at the inlet is the smallest and therefore generates the greatest pressure loss due to the flow resistance during flow. The diameter d2 of the opening 112b further away from the opening is larger than the diameter d1, and the diameter d3 of the opening 112c furthest away from the opening 108 at the inlet is the largest. In this way, the flow through the desiccant container can be made more uniform.Through the in . Figs. 33a , b With the air flow shown with flow through the desiccant bed 98, the service life of the desiccant can be significantly extended compared to the case of direct air ingress from the outside atmosphere into the facade cavity.

[0155] The desiccant is filled directly into an internal cavity of the main frame profile 6, so that no visual impairment is possible due to a desiccant container provided in the facade cavity. Furthermore, no separate desiccant container is required. The desiccant is replaced via an exchange device, as described with reference to Fig. 26 and 27 was explained.

[0156] In the Figuren 34a and 34b A second possible design is shown, where Fig. 34a represents a vertical section through the subframe profile in a cutting plane parallel to the glass plane of the facade element and Fig. 34b shows a vertical sectional view in a cutting plane perpendicular to the glass plane.

[0157] The design of the subframe profile according to Fig. 34a is similar to that according to Fig. 30 and differs only in that instead of the second pressure equalization opening between the inner cavity 96 of the subframe profile 7 and the facade gap 3, an opening 108 to the desiccant chamber is provided. The opening 108 is preferably a bore. For all other design features, please refer to the explanations for Fig. 30 be referred to.

[0158] The air flow through the desiccant bed 98 to Fig. 34b corresponds to that according to Fig. 33b .

[0159] Through the Figuren 34a , bWith the air flow shown with flow through the desiccant bed 98, the service life of the desiccant can also be significantly extended compared to the case of direct air ingress from the outside atmosphere into the facade cavity.

[0160] In the Figuren 35a and 35b A third possible design is shown, where Fig. 35a represents a vertical section through the subframe profile in a cutting plane parallel to the glass plane of the facade element and Fig. 35b shows a vertical sectional view in a cutting plane perpendicular to the glass plane.

[0161] The design of the subframe profile according to Fig. 35a is similar to that according to Fig. 31 and differs only in that instead of the second pressure equalization opening between the inner cavity 96 of the subframe profile 7 and the facade gap 3, an opening 108 to the desiccant chamber is provided. The opening 108 is preferably a bore. For all other design features, please refer to the explanations for Fig. 31 be referred to.

[0162] The air flow through the desiccant bed 98 to Fig. 35b corresponds to that according to Fig. 33b , however, with the difference that the opening 108 to the desiccant chamber is located vertically at the lower end of the facade element, and correspondingly, the openings 112a, 112b, 112c are located at the upper vertical end of the facade element. Due to the low volume flow of air, it makes no difference whether the desiccant bed 98 is flowed through from top to bottom or from bottom to top.

[0163] Through the Figuren 35a , bWith the air flow shown with flow through the desiccant bed 98, the service life of the desiccant can be significantly extended compared to the case of direct air ingress from the outside atmosphere into the facade cavity.

[0164] In the Fig. 35c und 35d is a further embodiment of the embodiment according to the Figuren 35a and 35b However, it should be clear that the adjustment options for pressure loss and preferred flow paths through the drying device described below can be applied to all embodiments in which the air flow is guided through the drying device for pressure equalization.

[0165] In the area of ​​the openings 112a, 112b and 112c, a sliding gate 122 is arranged, which is held in a suitable guide 124 so as to be displaceable in the axial direction in the direction of arrow A. In the sliding gate, the hatched in the Fig. 35c The apertures 126a, 126b and 126c shown are provided, which are movable by means of a displacement of the displacement link 122 between two positions which are in the Figuren 35c und 35d In the position shown Fig. 35c The apertures are located in an area that does not overlap the openings 112a, 112b, and 112c. Thus, there is no interaction between the openings 112a, 112b, and 112c and the apertures. Fig. 35d In the position shown, the orifice plate 126a is located in front of the opening 112a, the orifice plate 126b in front of the opening 112b, and the orifice plate 126c in front of the opening 112c. The pressure loss, as well as the flow pattern through the desiccant bed, can be influenced by the provision of openings in the orifices and their opening cross-sections. In the embodiment according to the Fig. 35c und 35d the aperture 126a has no opening, the aperture 126b has an opening with the diameter d1, and the aperture 126c has an opening with the diameter d2. In the position according to Fig. 35d Thus, opening 112a is closed. Opening 112b is narrowed to a diameter d1, and the opening 112b is narrowed to a diameter d3. This increases the pressure loss through the desiccant bed, but also prevents the flow path between openings 108 and 112a.

[0166] In the Figuren 36a and 36b A fourth possible configuration is shown, where Fig. 36a represents a vertical section through the subframe profile in a cutting plane parallel to the glass plane of the facade element and Fig. 36b shows a vertical sectional view in a cutting plane perpendicular to the glass plane.

[0167] The design of the subframe profile according to Fig. 36a is similar to that according to Fig. 32 and differs only in that instead of the second pressure equalization opening between the inner cavity 96 of the subframe profile 7 and the facade gap 3, an opening 108 to the desiccant chamber is provided. The opening 108 is preferably a bore. For all other design features, please refer to the explanations for Fig. 32 be referred to.

[0168] The air flow through the desiccant bed 98 to Fig. 36b corresponds to that according to Fig. 33b , so that the explanations for the Fig. 33b is referred to.

[0169] Through the Figuren 36a , b With the air flow shown with flow through the desiccant bed 98, the service life of the desiccant can be significantly extended compared to the case of direct air ingress from the outside atmosphere into the facade cavity.

[0170] In the Figuren 37a and 37bA fifth possible configuration is shown, where Fig. 37a represents a vertical section through the subframe profile in a cutting plane parallel to the glass plane of the facade element and Fig. 37b shows a vertical sectional view in a cutting plane perpendicular to the glass plane.

[0171] The design of the subframe profile according to Fig. 37a comprises a front cover 88 as in the embodiment according to Fig. 35a , but with additional transverse bulkheads 106 in the forward cover 88 for flow deflection and as dust collectors. The transverse bulkheads 106 create a tortuous flow path and further improve the effectiveness of the pressure equalization system.

[0172] The air flow through the desiccant bed 98 to Fig. 37b corresponds to that according to Fig. 35b , so that the explanations for the Fig. 35b is referred to.

[0173] Through the Figuren 37a , bWith the airflow shown, with flow through the desiccant bed 98, the service life of the desiccant can be significantly extended compared to the case of direct air ingress from the outside atmosphere into the facade cavity. This solution also has good dust separation properties due to the alternating transverse bulkheads in the front attachment element.

[0174] The design according to the Figuren 37a , b already generates a relatively high pressure loss in the air duct of the pressure equalization device, which can be problematic if the desiccant bed 98 also causes a high pressure loss during the flow, so that in the case of small pressure fluctuations there may not be a sufficiently high driving force for an air flow through the entire height of the desiccant bed 98, which essentially corresponds to the height of a facade element.

[0175] Therefore, the following are based on the Figuren 38a bis 42b In the embodiments described above, the opening 108 between the subframe profile 7 and the main frame profile 6 is arranged substantially centrally with respect to the height of the desiccant bed 98, while the openings 112a, 112b, ... are arranged above and below with respect to the desiccant bed 98. In this way, the distance between the opening 108 and each of the openings 112a, 112b, ... is halved.

[0176] The simplest case is in the embodiment according to the Figuren 38a und 38b shown, where Fig. 38a represents a vertical section through the subframe profile in a cutting plane parallel to the glass plane of the facade element and Fig. 38b shows a vertical sectional view in a cutting plane perpendicular to the glass plane.

[0177] Adjacent to a shortened air duct in the subframe profile 7 between the first pressure equalization opening 82 and the opening 108, the opening 108 is located approximately halfway up the facade element. This shortens the air path from the opening 108 to one of the openings 112a, 112b, resulting in a correspondingly lower pressure loss of the air as it flows through the desiccant bed 98. The pressure loss in the inner cavity of the subframe profile 7 is significantly lower than in the desiccant bed 98. The design in the subframe profile 7 corresponds to that in the Fig. 33a was shown, but with the modification that the opening 108 is located halfway up.

[0178] In the design according to the Figuren 39a, 39b shows Fig. 39a represents a vertical section through the subframe profile in a cutting plane parallel to the glass plane of the facade element and Fig. 39b a vertical sectional view in a cutting plane perpendicular to the glass plane.

[0179] The design of the subframe profile according to Fig. 39a corresponds to that according to Fig. 38a In the desiccant bed 98, in the example according to Fig. 39a However, six openings 112a, 112b, 112c, 112d, 112e and 112f are provided, which are designed as bores whose diameter increases with increasing distance from the opening 108, as already shown in the Fig. 33b explained. Two measures are thus combined in order to ensure that the desiccant fill 98 flows as evenly as possible while maintaining an acceptable pressure loss: on the one hand, the arrangement essentially vertically in the center of the opening 108 between the main frame profile 6 and the sub-frame profile 7, and on the other hand, the arrangement of the openings 112a to 112f in the façade cavity above and below in relation to the desiccant fill 98 with the opening cross-section of the openings increasing the further they are located from the opening 108 to the sub-frame profile.

[0180] The functional principle according to Fig. 39b can be combined with different flow guides in the subframe profile, whereby only one adjustment has to be made because the opening 108 in the main frame profile is located approximately halfway up the subframe profile.

[0181] When designing according to Fig. 40a the height of the cover 88 is higher than the design according to Fig. 34a reduced to half, while the design according to Fig. 41a the front cover 88 of those according to Fig. 35a and only the position of the opening 108 is changed. The flow guidance through the desiccant between the subframe profile and the facade cavity according to the Fig. 40b and 41b corresponds to that which was made with reference to Fig. 39b has already been explained.

[0182] When designing according to Fig. 42a, b the flow guidance between the opening 108 to the subframe profile 7 and the openings 112a, 112b, 112c, 112d, 112e and 112f corresponds again to that according to Fig. 39b However, in subframe profile 7, a Fig. 36a A shortened insert 100 with transverse bulkheads 106 is arranged to accommodate the modified position of the opening 108. This design with a shortened flow path through the subframe profile has the additional advantage that the pressure loss of the flow path through the subframe profile is also reduced.

[0183] When designing according to the Fig. 43a, b The opening 108 between the subframe profile 7 and the chamber filled with the desiccant in the main frame profile 6 is connected to a distributor pipe 114, so that air flowing into the drying device through the opening 108 enters the distributor pipe. The distributor pipe 114 is provided at predetermined intervals with a plurality of outlet openings 116a, 116b, 116c, 116d, 116e, the number of which differs from that according to Fig. 43b may vary. In the illustrated embodiment, the cross-sectional openings of the outlet openings 116a to 116e are not the same, but increase with increasing distance from the opening 108. In this way, the air flow exiting the individual outlet openings 116a to 116c can be influenced such that it is essentially the same size through each outlet opening. The openings 112a, 112b, 112c, 112d and 112e are each located essentially vertically above one of the outlet openings 116a to 116e, so that a preferred pad for the air flow is created between the pairs of one outlet opening 116a to 116e and one opening 112a to 112e, and the resulting distribution of the air flows through the desiccant bed achieves the most uniform possible loading of the desiccant in the drying device. The openings 112a to 112e have an increasing opening cross-section.In the case of a bore, the opening diameter of the openings 112a to 112e shown in . Fig. 43a marked d1 to d5, increases continuously from d1 to d5.

[0184] The embodiment according to the Fig. 44a und 44b changes the embodiment according to the Figuren 43a und 43b in that an additional Figuren 35c und 35dThe previously explained adjustability of the pressure loss of the air flowing through the drying device is provided. For this purpose, the distributor pipe 114 is surrounded by a pipe sleeve 118, which is rotatably mounted relative to the distributor pipe 114 via a plain bearing in the main frame profile 6 and is adjustable from the outside. For this purpose, the pipe sleeve 118 can be rotated from the outside on the main frame profile in the direction of arrow R. The pipe sleeve 118 has an adjustment opening 120a to 120e at each of the axial positions that correspond to the respective axial positions of the outlet openings 116a to 116e. By rotating the pipe sleeve 118 relative to the distributor pipe 114, the opening cross-section of the outlet openings 116a to 116e can be reduced. As the opening cross-section of the outlet openings decreases, the pressure loss of the air flow increases as it flows through the outlet openings 116a to 116e.

[0185] However, the air flows indicated in all figures are merely intended to schematically indicate a possible flow pattern. In reality, the air flow branches through a bed of granular solids, and the very low volume flows required for pressure equalization are also overlaid by diffusion processes that allow moisture-laden air to diffuse into areas where the air is dry. These diffusion processes support the uniform loading of the desiccant in the desiccant bed.

[0186] What all designs with air flow through the desiccant fill have in common is that the service life of the desiccant can be significantly increased compared to direct air flow into the façade cavity. This allows a double-skin façade element to be designed whose replacement interval can be more than 20 years, even under adverse climatic conditions, despite the omission of a capillary tube.

[0187] For all the air flow variants described above, the air flow rate as a function of the applied pressure difference can be determined with the help of a simple experiment. Targeted experiments can determine the relationship between the air flow rate and the pressure difference, allowing it to be described mathematically. The calculation of the pressure difference over a freely selectable reference period, e.g., one year, using hourly weather data for a defined location has already been explained in detail.

[0188] All of the illustrated embodiments, some of which are detailed illustrations, have in common that the facade element according to the invention can be designed in two different ways. Firstly, one surrounding frame profile can be provided for all components of the facade element, with either only transparent glass elements being provided, or transparent areas and additional opaque areas being provided, preferably in the parapet area. Secondly, two surrounding frame profiles can be provided: one surrounding frame profile for the transparent glass elements and another surrounding frame profile for the opaque area.

[0189] The facade element according to the invention inherently possesses an air volume in the cavity that far exceeds the gas volume of a conventional insulating glass pane. Therefore, the design options for insulating glass panes cannot be transferred to double-skin facade elements, and regular regeneration of the desiccant is required. Therefore, all functional elements, and in particular the pressure equalization device and drying device, must be accessible, maintainable, repairable, and replaceable. Furthermore, the pressure equalization device and drying device are arranged and dimensioned such that they are not located in a transparent area of ​​the facade element. This has the advantage of being fully integrated into the area of ​​the surrounding frame profile and thus completely concealed from outside observers. List of reference symbols

[0190] 1Facade element 2Outer glass element 3Facade cavity 4Inner glass element 5Solar protection 5'Sun protection in the parapet area 6Main frame profile of the surrounding frame profile 6a, 6bMain frame profile sections 7Subframe profile of the surrounding frame profile 8Seal 9Connecting screw 10Outer glazing bead 11Surrounding frame profile 12Transparent area 13Hollow chamber in the main frame profile 14Desiccant 15Opening 16Desiccant exchange device 17Pressure equalization subsystem between subframe profile and drying device in the main frame profile 18Pressure equalization opening 18aInsulation opening 19Desiccant container 20Glazed bead 21Air guide element 23aFoil 23bFoil 24Insulating bar 25Inner seal of the outer glass element 26Inner seal of the outer glass element 27Seal 28inner Expansion joint seal 29 Middle expansion joint seal 30 Outer expansion joint seal 31 Inner seal or inner seal 32 Seal inside the inner glass element 33 Outer seal 34 Pressure equalization opening35Long capillary tube 36Filter 37Pressure equalization opening 38Groove 39Plastic profile 41Receiving groove 42Pressure equalization opening 43Maintenance opening 44Connection piece 45Membrane 46Cavity 47Plastic profile 48Gap 49Plastic profile 50Gap 51Groove 53Groove 55Gap 56Vapour barrier 57Seal inside the inner panel 58Parapet panel (opaque) 59Outer cover shell of the parapet panel facing the room 60Opaque coating 61Inner cover shell of the parapet panel facing the room 62Insulating material 63Sealing part 64Room-side sealing element 65Inner cavity of the exchange device 66Plastic profile 67Cavity 68Opening 69Cavity of the desiccant container 70Filter 72Pressure equalization opening 74Recess 78Expansion joint 80Hollow chamber in the subframe profile 82First pressure equalization opening 84Second pressure equalization opening 86Corner angle 88Protruding cover 90Inner cavity of the cover 92Sleeve 94Third air equalization opening 96Inner cavity of the subframe profile 98Desiccant filling 100Insertion element102First wall 104Second wall 106Transverse bulkhead 108Opening to desiccant chamber 110Inner cavity of the main profile frame 112a... 112fOpening to the facade cavity 114Distribution pipe 116a...116eExit opening 118Pipe casing 120a...120eAdjustment opening 122Sliding gate 124Guide 126a, 126b, 126cPanel

Claims

1. Double-skin façade element, comprising: - a planar outer glazing element (2) and a planar inner glazing element (4) which are held at a distance from one another in a thermally insulated surrounding frame profile (6, 7); - at least one pressure equalization device (80, 13, 35; 41) which is in air-conducting connection with the outside atmosphere and with a façade intermediate space (3) which is provided between the outer glazing element (2) and the inner glazing element (4); - at least one drying device (80, 19, 13) fillable with desiccant (14) which is either arranged in the façade intermediate space (3) or is integrated into the surrounding frame profile (6, 7) and exchanges air with the façade intermediate space (3); wherein - at least one capillary element (35, 44, 46, 47, 49, 50, 66) is provided, which is an integral part of the surrounding frame profile (6, 7) and is preferably formed in part by a portion of the surrounding frame profile; - the pressure equalization device (80, 13, 35; 41) and the drying device (80, 19, 13) are positioned and dimensioned such that they do not extend into a transparent region of the façade element (1); and - the at least one drying device is designed to allow the desiccant to be replaced and preferably comprises a replacement opening configured to allow the desiccant to be replaced from the room side.

2. Double-skin façade element according to claim 1, characterized in that the at least one capillary element comprises a membrane (45) with a capillary tube (46), the capillary tube (46) having a length of at most 60mm and preferably of at most 20mm and particularly preferably of at most 10mm, and an inner diameter of at most 1.5mm and preferably of at most 1.0mm.

3. Double-skin façade element according to claim 2, characterized in that the at least one capillary element comprises a capillary tube (35) which has a length of at least 200 mm and preferably a membrane or a filter (36) or a strainer at the opening of the capillary tube (35) to the outside atmosphere.

4. Double-skin façade element according to any of the preceding claims, characterized in that the at least one capillary element comprises a capillary tube (35) that is fully integrated into the surrounding frame profile of the façade element, preferably clipped into the surrounding frame profile.

5. Double-skin façade element according to any of claims 1 to 3, characterized in that - the drying device comprises a desiccant container (19); and - the at least one capillary element comprises a capillary tube (35) which is integrated into the desiccant container.

6. Double-skin façade element according to any of claims 1 to 3, characterized in that - the drying device comprises a desiccant container (19); and - the at least one capillary element comprises a capillary tube (46) which is formed from a groove (74) in the desiccant container (19) and a wall of the surrounding frame profile (6).

7. Double-skin façade element according to any of claims 1 or 3, characterized in that the capillary element comprises a groove (38; 53) in the surrounding frame profile (6, 7) and an end profile (49, 66) made of plastic, a cavity (48; 50; 51; 55) being formed between the end profile and at least one inner wall of the groove (38; 53).

8. Double-skin façade element according to any of the preceding claims, characterized in that the double-skin façade element further comprises - means for reducing vapor diffusion, wherein - the means for reducing vapor diffusion comprise - wet glazing and - at least one insulation web (24) for thermal separation in the thermally insulated surrounding frame profile (6) made of a plastic with high vapor tightness and / or with a coating material (23a, 23b) with high vapor tightness.

9. Double-skin façade element, comprising: - a planar outer glazing element (2) and a planar inner glazing element (4) which are held at a distance from one another in a thermally insulated surrounding frame profile (6, 7); - at least one pressure equalization device (80, 13, 35; 41) which is in air-conducting connection with the outside atmosphere and with a façade intermediate space (3) which is provided between the outer glazing element (2) and the inner glazing element (4); - at least one drying device (80, 19, 13) fillable with desiccant (14) which is either arranged in the façade intermediate space (3) or is integrated into the surrounding frame profile (6, 7) and exchanges air with the façade intermediate space (3), wherein - the double-skin façade element further comprises means for reducing vapor diffusion, wherein - the means for reducing vapor diffusion comprise - wet glazing and - at least one insulation web (24) for thermal separation in the thermally insulated surrounding frame profile (6) made of a plastic with high vapor tightness and / or with a coating material (23a, 23b) with high vapor tightness; - the pressure equalization device (80, 13, 35; 41) and the drying device (80, 13, 35; 41) are positioned and dimensioned such that they do not extend into a transparent region (12) of the façade element (1); and - the at least one drying device is designed to allow the desiccant to be replaced and preferably comprises a replacement opening configured to allow the desiccant to be replaced from the room side.

10. Double-skin façade element according to claim 9, characterized in that the at least one pressure equalization device comprises a capillary element (35, 44, 46, 47, 49, 50, 66).

11. Double-skin façade element according to any of claims 1 to 10, characterized in that the pressure equalization device comprises a cavity (80) that includes an opening into the façade intermediate space (3); and the cavity (80) is filled with desiccant (14).

12. Double-skin façade element according to any of the preceding claims, characterized in that an opening in one of the at least one pressure equalization devices (80) is in flow connection with a second opening in a cavity (13) fillable with desiccant (14) of one of the at least one drying devices.

13. Double-skin façade element according to any of the preceding claims, characterized in that the drying device comprises a desiccant container fillable with desiccant that is removably attachable to the surrounding frame profile (6).

14. Double-skin façade element, comprising: - a planar outer glazing element (2) and a planar inner glazing element (4) which are held at a distance from one another in a thermally insulated surrounding frame profile (6, 7); - at least one pressure equalization device which is in air-conducting connection with the outside atmosphere and with a façade intermediate space (3) which is provided between the outer glazing element (2) and the inner glazing element (4), and an air routing device, wherein - the pressure loss of the air flow during pressure equalization is determinable and preferably adjustable by the length and / or the cross-sectional dimensions of the air routing device and / or the number of deflections of the air flow passing through the air routing device; - at least one drying device (80, 19, 13) fillable with a desiccant bed (98) which is integrated into the surrounding frame profile (6, 7), wherein - the at least one drying device comprises at least one first opening which is in air-conducting connection with the façade intermediate space; - the at least one pressure equalization device and the at least one drying device (80, 19, 13) are positioned and dimensioned such that they do not extend into a transparent region of the façade element (1), and - the at least one drying device is designed to allow the desiccant to be replaced and preferably comprises a replacement opening configured to allow the desiccant to be replaced from the room side.

15. Double-skin façade element, comprising: - a planar outer glazing element (2) and a planar inner glazing element (4) which are held at a distance from one another in a thermally insulated surrounding frame profile (6, 7); - at least one pressure equalization device which comprises an air routing device and is in air-conducting connection with the outside atmosphere and with a façade intermediate space (3) which is provided between the outer glazing element (2) and the inner glazing element (4); - at least one drying device (80, 19, 13) fillable with a desiccant bed (14, 98) which is integrated into the surrounding frame profile (6, 7), wherein - the at least one drying device (80, 19, 13) comprises at least one first opening which is in air-conducting connection with the facade intermediate space, and at least one second opening, which is in air-conducting connection with the air routing device; - the pressure loss of the air flow during pressure equalization is determinable and preferably adjustable by the pressure loss on flowing through the at least one drying device and the air routing device; - the at least one pressure equalization device and the at least one drying device (80, 19, 13) are positioned and dimensioned such that they do not extend into a transparent region of the façade element (1); and - the at least one drying device is designed to allow the desiccant to be replaced and preferably comprises a replacement opening configured to allow the desiccant to be replaced from the room side.

16. Double-skin façade element according to any of the preceding claims, characterized in that desiccant consumption over a given period of time can be estimated as a function of a location of the façade element, the type of desiccant and the design features of the façade element.

17. Double-skin façade element according to one of claims 14 and 16, characterized in that the air routing device comprises a cover (88) attachable to the surrounding frame profile (6, 7) which is preferably screwed or clipped onto the sub-frame profile.

18. Double-skin façade element according to claim 17, characterized in that the attachable cover (88) is made of a plastic with water adsorption capacity.

19. Double-skin façade element according to any of claims 16 to 18, characterized in that the air routing device comprises deflector elements (106) which can be used to create a winding flow path for the air through the air routing device (88).

20. Double-skin façade element according to any of claims 1 to 19, characterized in that the at least one drying device is integrated into cavities of the elements of the surrounding frame profile (6, 7) arranged vertically in the installation position.

21. Double-skin façade element according to any of claims 1 to 19, characterized in that the at least one drying device can be integrated both into cavities of the elements of the surrounding frame profile (6, 7) arranged vertically in the installation position and into cavities of the elements of the surrounding frame profile (6, 7) arranged horizontally in the installation position.

22. Double-skin façade element according to any of claims 1 to 21, characterized in that the double-skin façade element further comprises - means for reducing vapor diffusion, wherein - the means for reducing vapor diffusion comprise - wet glazing and - at least one insulation web (24) for thermal separation in the thermally insulated surrounding frame profile (6) made of a plastic with high vapor tightness and / or with a coating material (23a, 23b) with high vapor tightness.

23. Double-skin façade element according to claim 8, 9 or 22, characterized in that the means for reducing vapor diffusion include insulation webs (24) comprising a coating material (23a, 23b) with high vapor tightness, the coating material being applied all around mitered corners of the surrounding frame profile, the coating material preferably being applied to the entire frame perimeter including mitered corners.

24. Double-skin façade element according to one of claims 22 or 23, characterized in that the insulation web (24) is coated with a foil of thin stainless steel or butyl, or the insulation web (24) is made of a metalized plastic.

25. Double-skin façade element according to any of claims 22 to 24, characterized in that the insulation web (24) is made at least partially of polyvinylidene fluoride.

26. Double-skin façade element according to any of the preceding claims, characterized in that the surrounding frame profile (6, 7) comprises a main frame profile (6) and a sub-frame profile (7), wherein the main frame profile (6) and the sub-frame profile (7) are detachably connected to each other via connecting means (9) and the sub-frame profile (7) holds the outer glazing element (2).

27. Double-skin façade element according to claim 23, characterized in that a gasket (8) is arranged between the main frame profile (6) and the sub-frame profile (7), the gasket preferably being vapor-tight.

28. Double-skin façade element according to claim 26 or 27, characterized in that the at least one pressure equalization device (80, 13) is arranged in the main frame profile (6) or in the sub-frame profile (7).

29. Double-skin façade element according to any of the preceding claims, further comprising at least one solar shading device (5) in the façade intermediate space (3) between the outer glazing element (2) and the inner glazing element (4), the solar shading device (5) preferably being designed to be adaptive.

30. Double-skin façade element according to any of the preceding claims, characterized in that the inner glazing element (4) comprises either multi-pane insulating glass, preferably with two or three panes, or vacuum insulating glass.

31. Double-skin façade element according to any of the preceding claims, characterized in that the outer glazing element (2) is provided as monoglass, preferably as laminated glass or laminated safety glass, and preferably comprises at least one functional layer (60), particularly preferably a wavelength-selective coating.

32. Double-skin façade element according to any of the preceding claims, characterized in that the drying device comprises a cavity fillable with desiccant which is an integral part of the surrounding frame profile (6) and has a replacement opening that is configured to allow the desiccant to be replaced.

33. Double-skin façade element according to any of the preceding claims, characterized in that the at least one pressure equalization device comprises an elastic profile (66) with at least one opening (68) which is arranged in an air-conducting connection path between the façade intermediate space (3) and the outside atmosphere.

34. Double-skin façade element according to any of the preceding claims, further comprising an opaque inner element (58) and an outer element (2, 60) which are held at a distance from one another, the outer element preferably being transparent.

35. Double-skin façade element according to claim 34, characterized in that the opaque inner element (56) and the transparent outer element (2) are held in a further surrounding frame profile.

36. Double-skin façade element according to any of the preceding claims, characterized in that the pressure equalization device (80, 13, 35; 41) and the drying device (80, 19, 13) in the façade intermediate space (3) can be accessed by opening or removing the outer glazing element (2) or an opaque outer element (60) or the inner glazing element (4) or an opaque spandrel element (56).