Field of the Invention

The present invention concerns a skylight adapted for mounting over an opening in a roof construction.

Furthermore, the invention concerns a skylight band including a plurality of juxtaposed skylights. The invention moreover includes a window pane with an integrated solar cell.

Background of the Invention

Skylights for mounting on horizontal or inclining roof surfaces are prior art. The skylights may e.g. include a frame structure which is adapted for receiving a multi- layered glass pane (usually called a sealed insulating glass unit) and with an overlapping covering provided with a sealing strip along the periphery of the glass pane.

The frame structure is adapted such that the glass pane has an inclination for draining off water.

A drawback of such a construction is that the service life of the sealing strip is limited as it is exposed to the weather. This is particularly critical at the lower part of the skylight where rainwater is frequently collected. Over time, microscopic cracks will appear in the sealing strip which e.g. is made of butyl rubber. Alternating freezing and thawing will gradually widen the cracks in that rainwater penetrating into the cracks expands by freezing and contracts by thawing. The widened crack will then receive more rainwater such that it is further widened during the next period of frost. The rainwater will thereby gradually wedge its way through the sealing list until it breaks, begins to leak and has to be replaced. If such frame structures are made of wood, at first a possible surface coating and subsequently the underlying wood in the area under the sealing strip will gradually disintegrate and be filled with water-collecting cracks under the action of the above mentioned mechanism. If the skylight is not maintained by replacing particularly the lowermost sealing strip at regular intervals, rot and fungus may then appear in the frame structure with consequent increased speed of disintegration. Hereinafter there is a risk of immediate water ingress into the building during rainshowers, and the skylight has to be replaced entirely or partially. In order to increase the service life, aluminium profiles have therefore been introduced in the frame structure. Since aluminium has a high thermal conductivity, it has been necessary to accept a lower heat insulation capability for the skylight as a total in return for a prolonged service life.

Object of the Invention

It is the object of the invention to indicate a skylight and a band of skylights with improved service life. Another object of the invention is to achieve an improved energy balance for the skylight.

Description of the Invention

According to the present invention, this is achieved by a skylight adapted for mounting over an opening in a roof construction, including:

- a window pane which includes an external and an internal layer of glass disposed in parallel planes, and where the layers are spaced apart by spacer elements;

- a frame structure including connecting means for establishing a connection between the skylight and the roof construction, and retention means for retaining the window pane at the top side of the frame structure, where the frame structure has contact surface for the window pane, and where the frame structure is adapted such that the contact surface on the mounted skylight has an inclination relative to horizontal for draining off rainwater from the window pane in a draining direction under the action of gravity beyond a drain edge on the frame structure, which skylight is peculiar in that the external layer of the window pane has an extension relative to the internal layer of glass in a direction in parallel with the drain direction, where the extension is overlapping a part of the frame structure, and where the extension at least extends up to a vertical plane through the drain edge on the mounted skylight. Hereby is achieved that the skylight is provided improved service life as compared with prior art skylights as rainwater is readily conducted away from the skylight since there are no blocking constructional parts or sealing strips transverse to the direction of draining. As a consequence, it is also possible to make the skylight with an angle of inclination relative to horizontal approaching zero.

A skylight adapted for mounting on a flat roof surface is adapted such that the contact face for the window pane on the frame structure inclines towards a drain edge on the frame. This means that the distance from the contact surface to the roof surface close the drain edge is less than the distance to the roof surface farther from the drain edge. Rainwater will thus naturally run over the window pane with a flow or drain direction which is in parallel with the direction of the inclination and under the action of gravity. By the expression "farther from the drain edge" is meant a direction opposite the direction of draining or flow.

For a skylight adapted for mounting on a roof surface with an inclination, the distance of the contact surface to the roof surface close the drain edge of the frame structure can be identical to the distance to the roof surface farther from the drain edge of the frame structure, in addition to a lesser distance to the roof surface close to the drain edge and a greater distance to the roof surface farther from the drain edge as described above, if only the contact surface on the mounted skylight has an inclination against the drain edge of the frame structure such that rain water naturally will run over the window pane with a drain direction in the same direction as the inclination under the action of gravity and therefore in direction towards the drain edge.

Dewatering the skylight will occur at or beyond the drain edge of the frame structure. On a horizontal roof surface, the skylight may be freely oriented with the drain edge of the frame structure facing an arbitrary compass direction under consideration of the architecture and design of the building located under the roof surface and dewatering of the roof surface.

On a roof surface with inclination, the drain edge will typically be closest to the eaves such that rainwater is naturally conducted over the drain edge and towards the eaves to a gutter. Alternatively, the skylight can be oriented with the drain edge facing an arbitrary compass direction if only the inclination of the window pane relative to horizontal is directed towards the drain edge.

The window pane is made with an external and an internal layer of glass. These glass layers can be of the same type or of different types. For example, hardened, laminated or glass with different layer thickness can be applied, depending on the requirements to the skylight.

The layers are separated by spacers and kept together in a conventional way as in known sealed insulating glass units. The interspace between the layers may advantageously be filled with a gas, for example argon or krypton gas, or be subjected to vacuum such that the insulating capacity of the window pane is improved.

Typically, the frame structure rises above the roof surface, with external side faces and an internal clearance. The window pane is disposed on a contact surface of a frame structure that supports the window pane.

The connecting means may e.g. be brackets or a frame that overlaps an edge area around the window pane, with the exception of the edge area at the drain edge which is to be free so that rain water can run unhindered from the window. The external glass layer has an extension projecting over the internal glass layer.

The extension overlaps the part of the frame structure which is in the flow path of the rain water so that the rainwater is not stemmed up against the frame structure. The extension extends to a vertical plane through the drain edge on the mounted skylight. This is with regard to the inclination of the window pane. The rainwater can thus after leaving the external layer of glass drop or run vertically down along the external side of the frame structure.

The extension does not have the same insulating effect as the part of the window frame where an overlap exist between the two glass layers.

According to a further embodiment, the skylight according to the invention peculiar in that the extension extends past the vertical plane through the drain edge for forming a drip point.

Hereby is achieved that the rainwater falls freely without coming into contact with the frame structure after having left the external layer. Thus is achieved a further improvement of the service life of the skylight.

According to a further embodiment, the skylight according to the invention is peculiar in that the window pane includes a least one intermediate layer of glass disposed between the external and internal layers of glass.

Hereby is achieved that the window pane is provided a better insulating ability and that the skylight thereby is provided a better energy balance.

The said at least one intermediate layer of glass may advantageously be disposed so that it is spaced apart from the external and the internal glass layers. The separation is established by spacers at each side of the at least one layer of glass so that a further cavity is established for each intermediate layer of glass that is added. The cavity may advantageously be filled with a gas, e.g. argon or krypton gas, or be subjected to vacuum.

According to a further embodiment, the skylight according to the invention is peculiar in that the contact surface is formed in a recess in the frame structure, and that the recess in adapted for receiving at least part of the window pane. Hereby is achieved that the part of the retention means preventing movement of the window pane in a direction in the plane of the window pane can be avoided in a simple way.

Moreover, at substantial reduction of the heat transmission loss and thereby a better U-values is achieved as the recess acts as an insulating measure. Due to the extension of the external layer of glass beyond the frame structure, this improvement of the U- value is not achieved at the expense of the service life of the skylight as no moisture can be collected in the recess.

The recess is a depression in the frame structure such that the window pane is surrounded by the frame structure, and so that the heat transmission loss for the skylight is minimised.

The recess can have a recess so that it entirely or partially accommodates the thickness of the window pane.

According to a further embodiment, the skylight according to the invention is peculiar in that the top side of the overlapped part of the frame structure is countersunk relative to the top side of the non-overlapped part of the frame structure, and that the recess has a depth such that the window frame can be accommodated with the external layer of glass under the top side of the non-overlapped part of the frame structure for retaining the window pane in a direction in the plane.

Hereby is achieved that the draining away of rainwater from the skylight can be made particularly certain as the window pane can be fitted in the frame structure with its top side in a plane under the top side of the frame structure, thus making the window pane, which is optimised for a rapid draining of rainwater, lower that the frame structure around the window frame so that rainwater can be conducted from the frame structure to the window pane. According to a further embodiment, the skylight according to the invention is peculiar in that the retention means include a window covering for disposition over an edge area on the non-overlapping part of the window pane for retention in a direction out of the plane.

Hereby is achieved that the window pane is securely retained on the frame structure and that movement of the window pane in a direction out of the plane of the window pane can be prevented in a simple way. The window covering can be formed with a part situated at the top side of the frame structure and a part on the side of the frame structure. Hereby, a better protection against ingress of water in the frame structure is achieved. The end of the window covering at the side of the frame structure may advantageously consist of a bend so that a drip point is formed. The amount of rainwater running the whole way down along the side of the frame structure is limited hereby.

According to a further embodiment, the skylight according to the invention is peculiar in that it further includes a plurality of sealings that are disposed between the frame structure and the window pane.

Hereby, improved safety against ingress of rainwater into the frame structure is achieved.

According to a further embodiment, the skylight according to the invention is peculiar in that the design of the frame structure in a plane in parallel with a roof surface on the roof construction is optionally a closed polygon or a closed curve, preferably a triangle, quadrangle, circle or ellipse.

Hereby is achieved greater freedom to form the architectural expression of the skylight and the roof construction.

A triangular frame structure can be used with advantage alone or in connection with the formation of a pyramidal skylight band which is composed of three or more skylights. Each skylight forms a field in the skylight band, with each their inclination towards their respective drain edges.

A quadrangular design may advantageously be used alone or in connection with long skylight bands that include several interconnected skylights with the same inclination towards each their drain edge. The quadrangular design can also be used in a so-called ridge formation (rytter) where two elongated skylight bands are disposed back to back. A circular or elliptical skylight produces an architectural feature which may be desirable e.g. in connection with modern buildings. The drain edge may extend along half the circle or elliptical curve, beginning at each side of the window pane at the intersection between the curve and a straight line which is perpendicular to the inclination and which goes through the widest part of the window pane.

According to a further embodiment, the skylight according to the invention is peculiar in that the window pane includes an integrated solar cell.

Hereby it is possible to provide accessories for the skylight with electric power or to supply electric power to the building on which the skylight is mounted, or to the public network. In the two latter instances the supplied power may possibly be taken into account in the energy balance of the window.

According to a further embodiment, the skylight according to the invention is peculiar in that the window pane includes a window frame with a recess in which the internal and possibly intermediate layers of glass are inserted, where the external layer of glass is disposed with the extension overlapping in at least part of the window frame, and where the window pane includes a hinge which is fastened to the frame structure for opening the window, and a closing mechanism for closing the window. Hereby is achieved that the skylight can be made opening. This is suitable in connection with ordinary ventilation as well as fire ventilation. In the closed condition, the opening skylight has the same advantages as the non- opening skylight with regard to improved service life and possible improvements of the U-value. Examples of accessories for the skylight could be curtains, ventilation or lighting.

Transparent or semi-transparent solar cells can be applied which act as sun screens by themselves. Hereby too strong thermal radiation is avoided which otherwise had to be removed by cooling.

In a particular embodiment, the integrated solar cell is forming a pattern, for example a logo in one or more colours.

Furthermore, the object of the invention is achieved by a skylight band including a plurality of juxtaposed skylights as described above where the frame structure is shared by adjacent window panes.

Hereby is achieved possibility of covering a large continuous area of the roof surface with skylights. The advantages of the invention with regard to increased service life and limited demands on maintenance come particularly to advantage in connection with skylight bands where maintenance of prior art systems can be particularly resource demanding.

In a particular embodiment, the skylight according to the invention is peculiar in that the frame is made of a material selected among natural materials such as wood, plastic materials such as polycarbonate and polyamide, fibre reinforced composite materials such as glass fibre, or other materials with a low thermal conductivity (<0.3W/mK).

Hereby is achieved a particularly good value for the thermal conductivity of the skylight. In a particular embodiment, the skylight according to the invention is peculiar in that the frame structure is formed of one or more profiles with hollow core, and that the core is filled with insulating core material. Surprisingly, it has appeared that a skylight according to the invention with three layers of glass in the window pane and with a frame structure of wood enables achieving a calculated U- value according to DS 418, 6th edition, of 0.2 W/m ² K with a transmission area of 3.33 m ² . This is calculated for a skylight according to the invention where no krypton gas is used in the interspace between the individual layers in the window pane. By introducing krypton gas, an even lower value is expected.

In comparison can be mentioned that the Technical University of Denmark in a report from Department of Building and Construction, Report 2008, "Analyse af energikrav til vinduer i energimaerkningsordning og BR 2010, 2015 og 2020", propositions to requirements and energy label (table 13) have been drawn up:

It appears from the above that the skylight according to the invention already fulfils the requirements to energy label class 0 for the year 2020.

A further aspect solved by the invention is integration with the solar cell, contributing to an improved energy balance.

According to the invention, this is achieved by a window pane which includes an external, an intermediate and an internal glass layer located in parallel planes, where the layers are spaced apart by spacer elements for forming a first closed cavity between the external and the intermediate layer of glass, and a second cavity between the internal and the intermediate layer of glass, and where the window pane includes an integrated solar cell disposed on one of the glass layers optionally in the first or the second cavity. Since the solar cell is integrated in the cavities, a great advantage is achieved in addition to the improved energy balance as the solar cell is well protected.

The payback time for a skylight in which the window pane with the integrated solar cells is provided is furthermore shortened as the skylight supplies power for consumption.

Description of the Drawing

The invention will be explained in more detail below with reference to the accompanying drawing, where:

Fig. 1 shows a section along a centre plane through an embodiment of the skylight;

Fig. 2a shows a view of "detail 1" of Fig. 1;

Fig. 2b shows a view of "detail 2" of Fig. 1;

Fig. 3 a shows a section on the line A- A on Fig. 1 ;

Fig. 3b shows a view of "detail 3" of Fig. 3a;

Fig. 4 shows part of a skylight band;

Fig. 5 shows a detail of a vertical window as an alternative application of the technique described in the present application; and

Fig. 6 shows a sectional view through a ridge light with opening skylight. In the explanation of the Figures, identical or corresponding elements will be provided with the same designations in different Figures. Therefore, no explanation of all details will be given in connection with each single Figure/embodiment.

Detailed Description of Embodiments of the Invention

Figs. 1-3 show various sections and details of an embodiment of the skylight 1 according to the invention. The skylight 1 is adapted for mounting over an opening 2 in a roof construction, and in the embodiment of Figs. 1-3 it is adapted for mounting in a horizontal roof construction. A window pane 3 is mounted in the skylight 1. In the shown embodiment, the window pane 3 includes an external 4, an intermediate 5 and an internal 6 layer of glass disposed in parallel planes. The layers 4, 5, 6 are mutually separated by spacers 7.

The structure of the skylight is constituted by a frame structure 8 having connecting means (not shown) for establishing a connection between the skylight 1 and the roof construction under installation of the skylight 1.

The frame structure 8 has retention means 9 for retaining the window pane 3 at the top side 10 of the frame structure 8 where a contact surface 11 is provided for the window pane 3. The contact surface 11 is arranged with an inclination relative to horizontal when the skylight is mounted so that rainwater is drained away from the window pane in a draining direction 12 under the action of gravity over a lowly lying drain edge 13 on the frame structure 8. The external layer 4 of the window pane has an extension 14 extending farther than the intermediate 5 and internal 6 layers in a direction in parallel with the drain direction 12. The extension 14 overlaps part of the frame structure 8. The overlapped part 15 of the frame structure 8 is located opposite the drain edge 13. The extension 14 extends beyond a vertical plane through the drain edge 13 on the mounted skylight 1 such that a drip point 16 is formed from where rainwater can drip without hitting the side of the frame structure 8 if not influenced by the wind.

The contact surface 11 is formed in a recess 17 in the frame structure 8 in which the window pane 3 is accommodated.

The top side of the overlapped part 15 of the frame structure 8 is countersunk relative to the top side of the non-overlapped part 18 of the frame structure 8, and the recess 17 has a depth such that the window pane 3 can be accommodated with the external 4, the intermediate 5 and the internal 6 layers of glass under the top side of the non- overlapped part 18 of the frame structure 8. Thereby the window pane 3 cannot be dislocated in the plane once it is located in the recess 17. The window pane 3 is retained in the direction out of the plane by a window covering 19 which together with the recess 17 constitutes the retention means 9. The window covering 19 is located over an edge area 20 of the window pane 3 on the non-overlapping part of the frame structure 8.

By disposing the window pane 3 in a recess 17, a considerably reduced transmission loss is attained for the skylight 1, 1 '.

The skylight is provided with a number of sealings 21 disposed between the frame structure 8 and the window pane 3. The window pane 3 includes an integrated solar cell 32 provided on one of the glass layers 4, 5, 6. In the shown embodiment, the solar cell 32 is provided on the inner side of the external 4 layer of glass. Alternatively, the solar cell 32 can be disposed at the outer side or the inner side of the intermediate 5 layer of glass, or at the outer side of the internal 6 layer of glass. The solar cell 32 has electric connection (not shown) with the public network or other accessories for the skylight.

By a solar cell 32 is meant a single cell as well as a system comprising several cells.

In the practical embodiment on Figs. 1 to 3, the frame structure 8 is constructed by a framework of wooden laths 22 with plywood boards 23 at the sides, and a layer of insulating core material in the cavities 24. Moreover, the skylight 1 is provided with a vapour barrier 25 at the inner side, and two layers of plaster 26 as a final layer on the internal plywood board 24. The recess 17 is formed of other wooden laths 27 that are fastened at the top of the frame structure 8 and which is narrower than the underlying part of the frame structure 8. An aluminium covering 28 is provided upon the frame structure 8. The aluminium covering 28 is provided with a drip point 29. On the part 15 overlapped by the extension 14 of the frame structure 8, the aluminium covering 28' is disposed between the frame structure 8 and the overlapped part 15. The aluminium covering is also provided with a drip point 29'. Fig. 4 shows a part of a skylight band 30. A window pane 3 from a first skylight 1 is disposed on the part of the frame structure 8 shared by adjacent window panes 3. The shared part of the frame structure will be fastened at each end to the remaining part of the frame structure 8. Alternatively, several skylight windows according to the embodiment in Figs. 1-3 are juxtaposed, thereby forming a skylight band (not shown).

Fig. 5 shows a detail of a vertical window 31 as an alternative application of the technique described in the present application.

By a vertical inclination of the contact surface (not shown on Fig. 5) on the skylight 1, the invention can be applied in a window for installation in vertically walls in a building. Ample protection of sealings at the bottom of the window is achieved such that their service life is extended.

The window 31 includes a frame structure 8 that retains the window pane in the plane and retention means (not shown on Fig. 5) retaining the window pane out of the plane. The extension 14 of the window pane overlaps part of the frame structure 8 such that a sealing between the extension 14 and the frame structure 8 is protected against dammed or accumulated rainwater.

Fig. 6 shows a sectional view through a ridge light 32 with a non-opening skylight 1 and an opening skylight Γ, respectively. The ridge light 32 is mounted over an opening 2 in a roof construction. On Fig. 6, the roof construction is horizontal, but the ridge light 32 is also suited for mounting in a roof construction with inclining roof surfaces. The non-opening skylight 1 is designed like the embodiment on Figs. l-3b with a few exceptions.

The aluminium covering 28', which is provided on the part 15 of the frame structure 8 overlapped by the extension 14, is provided with a bend 33 - a so-called "haft" in this embodiment. The joint between the ridge light 32 and the roof construction is sealed by asphalt roofing 34 which is fastened to the top side of the roof construction and the side of the frame structure 8. The uppermost part of the asphalt roofing 34 is covered by an aluminium profile 35 which is bent such that the fits into the bend 33. Hereby is achieved a substantial saving in mounting time for the ridge light 33 as there is achieved a tight-fitting joint between the roof construction and the frame structure 8 in a simple way.

The same solution may furthermore be used in the skylight 1 on Figs. l-3b.

This solution is also used at the opposite side of the ridge light opposite the opening window Γ, but for the sake of clarity the reference numbers are omitted on Fig. 6.

The opening skylight is formed with a window pane 3' which includes a window frame 36 in which the layers 5, 6 of glass are inserted in a recess 37 whereas the external layer of glass 4 overlaps at least the lowermost part of the window frame.

The window frame 36 is fastened to the frame structure 8 by fastening means 9 in the form of a hinge 38 so that the window frame 3' can be opened, and a fastener (not shown) or corresponding closing mechanism spaced apart from the hinge so that the window can be kept closed.

The skylight Γ is formed with packings, sealings and coverings which counteract ingress of water and wind between the window frame 36 and the frame structure 8.

The window pane 3' is provided in the frame structure 8. Preferably, the frame structure 8 is formed with a recess 17', 17" adapted for accommodating the window frame 36 such that the extension 14 overlaps part of the frame structure 8. Hereby, the drip point 16 from where rainwater can drip without hitting the side of the frame structure 8 if not influenced by wind is formed. In the shown embodiment, the recess 17' at the lowermost part of the window is formed by a wooden lath 22, and a second wooden later 27, which is narrower than the first mentioned wooden lath 22, is placed upon the first mentioned wooden lath 22. The recess 17" at the uppermost part of the frame structure 8 is formed by a milling in the wooden lath 22 in the frame structure 8.

By disposing the window panes 3, 3' in each their recess 17, 17', 17", a considerably reduced transmission loss is attained for the skylight 1, 1 '.