Patent Description:
When installing windows in a roof, it is first and foremost vital to ensure that the roof window itself is tight, just as the connection between the window frame and the surrounding roofing material needs to be weatherproof. At the same time, the insulation properties of the window need to meet certain standards, and the manufacturing and installation of the roof window need to be carried out cost- and time-efficiently. Today, with increasing focus on design, however, it is also desirable to make the roof window itself and the transition between the roof window and the roof surface visually smooth and of a pleasant appearance in order for the roof including one or more roof windows to attain the overall appearance aimed at.

These requirements, which are often mutually contradicting, are challenging to meet to a full extent. Examples of prior art roof windows setting out to improve the performance on several of these parameters are found in i. <CIT>, <CIT>, <CIT> and <CIT>. Even though these roof windows have proven to function very well in practice, there is still room for improvement.

With this background, it is therefore an object of the invention to provide a roof window by which it is possible to improve the performance on some parameters without compromising others.

In a first aspect, this and further objects are achieved with a roof window according to claim <NUM>.

By forming the exterior sheet with an extended portion to overlap the bottom sash covering the extended portion having such a configuration and such dimensions that its projection shadows the underlying bottom sash covering and any other subjacent components, to at least a large extent, while at the same time providing a masking covering the extended portion, the bottom sash covering is effectively rendered inconspicuous in a simple manner. In turn, the roof window is given improved insulating properties due and an appealing look as the pane element extends throughout to the bottom of the roof window, thus smoothening the transition to the roof surface, or to another roof window located below in the direction of the roof inclination. Drainage of precipitation is facilitated as water, snow etc. is allowed to simply drip off the edge of the exterior sheet. Furthermore, the extended portion of the exterior sheet functions as an external weather screen for the bottom sash covering such that any fastening means such as screws securing the bottom sash covering to the sash are shielded from the weathering and in turn less exposed to penetration of water and other precipitation. Improved tightness at the sides of the pane element is provided in that the glazing profiles and the side sash coverings form a rim, thus channelling any precipitation over the edge of the exterior sheet.

The at least one masking may be provided on the interior face and/or on the exterior face of the extended portion of the exterior sheet of the pane element. Providing the masking on the exterior face has a number of advantages, but the masking will be more exposed to wind load and UV radiation. Masking provided on the interior side is not as exposed to wind load, and less exposed to UV radiation.

The masking preferably has a length substantially corresponding to the width of the extended portion of the exterior sheet of the pane element in the width direction of the roof window, and a width substantially corresponding to the length of the extended portion of the exterior sheet of the pane element in the length direction of the roof window. In this way, the masking covers the entire extended portion of the exterior sheet, thus effectively concealing any subjacent components of the roof window. In an advantageous further development in which the pane element comprises at least one spacer and optionally at least one outer sealant, the masking covers also the at least one spacer and optionally the at least one outer sealant.

While the invention is in principle applicable to roof windows having a two-layer pane element, with an exterior sheet and one interior sheet, the pane element of a presently preferred embodiment comprises a first and a second interior sheet positioned on the interior side of the exterior sheet, the first and second interior sheets preferably being of substantially identical size and have a common edge, the size of the first and second interior sheets substantially corresponding to the inner portion of the exterior sheet of the pane element. This configuration improves the insulation properties of the roof window even further.

In another presently preferred embodiment, the bottom sash covering comprises a main section adjoined by a depending section to one side and a shelf section to the other side, and the main section and the shelf section are located at a distance from the interior side of the extended portion of the pane element such that a gap is formed between the bottom sash covering and the extended portion of the pane element, preferably the main section of the bottom sash covering being curved and having an apex substantially level with the shelf section, more preferably the transition between the main section and the shelf section comprising an inclined bridge section. By this design, features of a traditional roof window have been incorporated into the bottom sash covering of the roof window according to the invention. The gap provided improves the insulation properties of the roof window even further. In addition, this means that manufacturing and storage costs may be reduced, and the installation of external accessories such roller shutters and awnings is facilitated.

In an advantageous development of this embodiment, at least one seal is provided to span the gap between the bottom sash covering and the extended portion of the pane element. This provides for increased protection against the surroundings and may also contribute to the retention of the pane element to the sash. In such embodiments, the presence of one or more seals between the extended portion of the pane element and the bottom sash covering provides for an excellent lifetime performance of the roof window. This applies in particular in the case of cover members of metal, which is known as a material providing a reliable bonding surface, just as the glass surface of the extended portion of the pane element.

Preferably, a first seal is provided at the main section and a second seal at the shelf section to span the gap between the bottom sash covering and the extended portion of the pane element. Thus, a two-step sealing action is provided, and different properties may be assigned to the first and the second seal.

A particularly efficient sealing action is provided by an embodiment, in which the second seal on the shelf section of the bottom sash covering is located close to the edge of the first and second interior sheets and the first seal on the main section of the bottom sash covering is located at a distance from the second seal, near the edge of the extended portion of the exterior sheet of the pane element.

Each seal may in principle be provided as through-going sealing profiles. However, in a particularly resourceful embodiment, the second seal comprises a plurality of distinct sealing elements, each sealing element having a longitudinal extension substantially smaller than the width of the extended portion of the exterior sheet of the pane element in the width direction of the roof window.

Additionally, or alternatively, the first seal comprises a sealing profile having a longitudinal extension substantially corresponding to the width of the extended portion of the exterior sheet of the pane element in the width direction of the roof window, the sealing profile preferably comprising a main body, an outer sealing lip and an inner sealing lip.

In a presently preferred embodiment, the masking is a provided as a coating, preferably as a ceramic coating burned into the glass of the exterior sheet during tempering thereof. This has proven to function particularly well, regardless of whether the masking is on the exterior or the interior face.

In a development of a presently preferred embodiment, in which the bottom sash covering comprises a main section adjoined by a depending section to one side and a shelf section to the other side, the depending section of the bottom sash covering is provided near the edge of the extended portion of the exterior sheet of the pane element, and wherein the depending section extends below the plane of the at least one interior sheet. This provides for excellent overall tightness of the roof structure.

In another development, the extended portion of the exterior sheet extends across and beyond the frame bottom member when looking in the plane of the pane element. This also improves the weatherproofing properties of the roof window.

In a presently preferred embodiment, at least one seal is a structural seal which retains the bottom of the pane element. This provides for a particularly reliable connection of the pane element to the sash. In a further development, which is particularly useful in embodiments in which a set of glazing clips is provided under the bottom sash covering, said at least one structural seal is located at or near said set of glazing clips. This provides for a reliable transmission of any load acting on the pane element to the subjacent glazing clips.

To increase in particular the appearance of the roof window, but also protection against for instance UV radiation, a secondary masking may be provided on at least one interior sheet of the pane element.

In a second aspect, a method of manufacturing a roof window is provided.

Referring initially to <FIG> and <FIG> in which a prior art roof window <NUM>' is shown, such a roof window <NUM>' comprises a frame <NUM>' configured to be built into roof structure and a sash <NUM>'. The sash <NUM>' is pivotally connected to the frame <NUM>' at a set of hinges <NUM>' Details of the prior art roof window <NUM>' shown in <FIG> are described in the above-mentioned <CIT> to which reference is hereby made. In a manner known per se, the roof window <NUM>' comprises a frame represented by frame bottom member <NUM>' connected to a roof structure <NUM> and a sash represented by sash bottom member <NUM>'. An insulating element <NUM>' is provided below bottom flashing <NUM>' and bottom frame covering <NUM>', having an abutment side <NUM>' on a ledge <NUM>' facing the frame bottom member <NUM>'. A further insulating element <NUM>' is provided under the bottom sash covering <NUM>'. It is seen how the bottom sash covering <NUM>' overlaps the lower portion of the exterior side of the pane <NUM>'.

Turning now first to <FIG>, a description of the general configuration of embodiments of a roof window <NUM> of the present invention will be given. Details not shown or described in detail correspond to the prior art roof window described in the above and/or are readily apparent to the person skilled in the art. In more detail, the roof window <NUM> defines a length direction and a width direction. In roof windows installed in an inclined roof surface, the length direction is normally parallel to the direction of inclination of the roof. The inclination of the roof typically ranges from <NUM>° to <NUM>°, but the roof window <NUM> according to the invention may be built into even very low pitch roofs, for instance having an inclination as low as <NUM>°. The width direction is perpendicular to the length direction. The roof window <NUM> comprises a frame <NUM>, a sash <NUM>, a pane element <NUM> comprising at least one interior sheet <NUM>, <NUM> and an exterior sheet <NUM>. Here, two interior sheets <NUM>, <NUM> are provided. The pane element <NUM> is connected to the sash <NUM> by means of a glazing profile <NUM> extending in the length direction of the roof window at each side of the pane element <NUM>. Thus, a total of two glazing profiles <NUM> are present here; however, further glazing profiles may in principle be provided also at the top and possibly at the bottom of the sash <NUM> and pane element <NUM>. A set of cover members includes a bottom sash covering <NUM> extending in the width direction of the roof window and a side sash covering <NUM> extending in the length direction of the roof window and connected to the sash <NUM>. Each side sash covering <NUM> has such a width that it extends over at least the glazing profile <NUM> and optionally over the pane element <NUM> at each side of the pane element <NUM>. The width and shape of the side sash covering <NUM> may in principle be chosen arbitrarily, as long as a suitable overlap is established relative to the glazing profile <NUM>, possibly thus also relative to the associated side edge of the pane element <NUM>. In the embodiment shown, each side sash covering <NUM> has an end 17a and a side flange 17b. At least the side flange 17b of the side sash covering <NUM> overlaps the glazing profile <NUM>, which in turn overlaps the pane element <NUM>, i.e. the exterior sheet <NUM>, at the sides thereof.

The sash <NUM> is openable relative to the frame <NUM>, which is stationary relative the roof structure. The sash <NUM> is pivotally connected to the frame <NUM> by means of a set of hinges <NUM> defining a hinge axis α located between a top and a bottom of the roof window <NUM>. Normally, the hinge axis α is located approximately in the middle, but other positions including positions closer to the top are conceivable as well. In such fields of application, in which the hinge axis is located somewhere between the middle and the top, an improved lifting performance of the hinge may be desirable. This also applies to roof windows installed in low pitch roofs. One example of a hinge meeting such requirements is shown and described in Applicant's <CIT>.

A bottom frame covering <NUM> is also provided, and two side frame coverings <NUM>, one at either side of the frame <NUM>. The side frame coverings <NUM>, together with the side sash coverings <NUM>, provide protection of the components below and drainage for water and other precipitation. The side sash coverings <NUM> interact with the frame side coverings <NUM> in a manner known per se, as they are located in overlapping extension of each other in the closed position of the roof window <NUM>, i.e. when the sash <NUM> is parallel to the frame <NUM>, and at the same time, opening of the sash <NUM> relative to the frame <NUM> is made possible by the particular configuration of the side frame coverings <NUM> and the sash side coverings <NUM>. An insulating element <NUM> is present below the bottom frame covering <NUM>. A flashing arrangement is provided as in the prior art, but not shown in the drawings of the embodiments of the invention.

According to the invention, the exterior sheet <NUM> of the pane element <NUM> is provided with an extended portion 43b extending beyond an inner portion 43a to an edge 43c at a distance from an edge <NUM> of the at least one interior sheet <NUM>, <NUM> and overlapping the bottom sash covering <NUM>, that at least one masking <NUM>; <NUM>: <NUM> is provided to substantially cover the extended portion 43b, and that each glazing profile <NUM> and each side sash covering <NUM> has such a length that they extend substantially to the edge 43c of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM>. Here the first and second interior sheets <NUM>, <NUM> are of substantially identical shape and have a common edge <NUM>, but other configurations could apply. The extended portion 43b overlaps the bottom sash covering <NUM>, and at least one masking <NUM> is provided to substantially cover the extended portion 43b. By the term "overlaps" it is understood that the extended portion 43b has such a configuration and such dimensions that its projection shadows the underlying bottom sash covering <NUM>, and any other subjacent components, to at least a large extent. This is qualified by the term "substantially covers", denoting that the majority of the bottom sash covering <NUM> is hidden below the masking <NUM>, possibly entirely invisible or undiscernible. Also visible in <FIG> are spacers <NUM> and <NUM> arranged between the first and second interior sheets <NUM>, <NUM>, and between the second interior sheet <NUM> and the exterior sheet <NUM>, respectively. On the outer side of the spacers <NUM>, <NUM>, respective outer sealants 45a and 46a are present.

The masking <NUM> may be provided on the interior face, on the exterior face or both faces of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM>. As shown in <FIG>, the masking <NUM> is provided on the internal face e.g. inner portion of exterior sheet 43a. The masking <NUM> may extend to cover the spacers <NUM>, <NUM> also, and the respective outer sealants 45a, 46a. In such case the spacer <NUM> may be sealed to the masking <NUM> rather than to the glazing surface as usually. The term "masking" is to be interpreted as a separate component or treated surface of the exterior sheet <NUM> of the pane element <NUM>, applied closely and in contact with the exterior sheet <NUM>. The masking <NUM> may in principle be made in any suitable manner. For example by a film or printing, or enamel or ink. Here, however it is provided as a coating, preferably as a ceramic coating sintered to the glass of the exterior sheet <NUM> during tempering thereof. A particularly well-functioning coating is the commercially available Ferro System <NUM>. The masking <NUM> may comprise an aperture for a sensor for example light sensor or rain sensor etc..

The position and the extension of the masking, or maskings, on the pane element <NUM> may be chosen depending on a variety of parameters such as material, manufacturing conditions, configuration of other parts of the window, climate zone of the roof window installation etc. Also indicated in <FIG> is a secondary masking <NUM> is provided on interior sheet <NUM> of the pane element <NUM>. The secondary masking <NUM> extends up to the position where the sash bottom member <NUM> no longer covers the interior pane <NUM>.

In the alternative, second embodiment of <FIG>, one masking <NUM> is provided on the internal face of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM>. The extension in the length direction is slightly smaller than in the embodiment shown in <FIG>.

Referring now to the alternative embodiment of <FIG>, the masking <NUM> is provided on the exterior face. Here, it is also shown that the masking <NUM> has a length L substantially corresponding to the width of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM> and a width W substantially corresponding to the length of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM>. The length of the extended portion 43b substantially corresponds to the distance between the edge <NUM> of the interior sheet(s) <NUM>, <NUM> and the edge 43c of the extended portion 43b. In practice, roof windows come in various sizes within a predefined size programme, and the length of the extended portion 43b and hence the width W of the masking <NUM> will be constant for windows of varying sizes and amount to for instance <NUM> to <NUM>, whereas the width of the extended portion 43b, corresponding to the length W of the masking <NUM> follows the width of the window size, typically <NUM> to <NUM>. The length and width indications apply also the embodiments relating to masking <NUM> and masking <NUM>.

Referring now also to <FIG>, the bottom sash covering <NUM> comprises a main section <NUM> adjoined by a depending section <NUM> to one side and a shelf section <NUM> to the other side, and wherein the main section <NUM> and the shelf section <NUM> are located at a distance from the interior side of the extended portion 43b of the pane element <NUM> such that a gap <NUM> is formed between the bottom sash covering <NUM> and the extended portion 43b of the pane element <NUM>. The depending section <NUM> of the bottom sash covering <NUM> forms a skirt portion near the edge 43c, which extends below the plane of the interior sheets <NUM>, <NUM>.

In the embodiment shown, the extended portion 43b of the exterior sheet <NUM> extends across and beyond the frame bottom member <NUM> when looking in the plane of the pane element <NUM>.

In the embodiments shown, at least one seal <NUM>, <NUM> is provided to span the gap <NUM> between the bottom sash covering <NUM> and the extended portion 43b of the pane element <NUM>. A first seal profile <NUM> is provided at the main section <NUM> and a second seal <NUM> at the shelf section <NUM> to span the gap <NUM> between the bottom sash covering <NUM> and the extended portion 43b of the pane element <NUM>.

As shown in <FIG>, the second seal of this embodiment comprises a plurality of distinct sealing elements <NUM>, where each sealing element <NUM> has a longitudinal extension substantially smaller than the width of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM> in the width direction of the roof window. Referring briefly again to <FIG>, a set of glazing clips <NUM> is provided under the bottom sash covering <NUM>, and two sealing elements <NUM> are located at or near each set of glazing clips <NUM>. The number of glazing clips <NUM> may in principle depend on the width of the roof window <NUM>, but two glazing clips <NUM> are typically present.

In the first embodiment, the first seal comprises a sealing profile <NUM> having a longitudinal extension substantially corresponding to the width of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM> in the width direction of the roof window. The sealing profile <NUM> comprises a main body <NUM> configured to be placed on the main section <NUM> of the bottom sash covering <NUM>. From the main body <NUM>, an outer sealing lip <NUM> and an inner sealing lip <NUM> protrude to contact the interior side of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM>.

In the alternative embodiments of <FIG> and <FIG>, the first and second seals are provided as a first sealing profile <NUM>, <NUM> and a second sealing profile <NUM>, <NUM>. The sealing profiles may in principle take any suitable form, confer the other embodiment of sealing profile <NUM> of <FIG>.

The seals are typically made of reliable sealants, for instance polyurethane and/or silicone sealants. Adhesive tapes and/or gaskets like for example rubber or neoprene gaskets can also be used. The seals <NUM> and <NUM> can each employ a different seal so for example the seal <NUM> may be a structural seal and the seal <NUM> may be a regular seal. When a seal is structural it bonds to the pane <NUM> and has a pane retaining effect which makes mechanical fasteners needless. In one example the seal <NUM> is an adhesive tape and the seal <NUM> is a gasket.

The second seal <NUM> on the shelf section <NUM> of the bottom sash covering <NUM> is shown located close to the edge <NUM> of the first and second interior sheets <NUM>, <NUM>, and the first seal <NUM> on the main section <NUM> of the bottom sash covering <NUM> is located at a distance from the second seal <NUM>, closer to the edge 43c of the extended portion 43b of the exterior sheet <NUM> of the pane element <NUM>.

The shape of the bottom sash covering <NUM> is made to resemble the shape of its prior art counterpart, however with a number of differences to be able to be positioned entirely below the extended portion 43b of the exterior sheet. Hence, the main section <NUM> of the bottom sash covering <NUM> is here curved and has an apex 151a substantially level with the shelf section <NUM>.

Furthermore, the transition between the main section <NUM> and the shelf section <NUM> comprises an inclined bridge section <NUM>. On the shelf section <NUM>, two mounting holes <NUM> are formed to receive fastening means such as screws in order to secure the bottom sash covering <NUM> to parts of the sash bottom member <NUM>, details not shown. At either longitudinal end of the shelf section <NUM>, a tab 155a is provided. At either longitudinal end of the main section <NUM>, a side section <NUM> is provided, with an upstanding end section <NUM>, and with respective mounting hole <NUM> for securing to underlying components of the sash bottom member <NUM>.

The exploded partial perspective view <FIG> shows the side sash covering <NUM>, the glazing profile <NUM> and a sash profile seal <NUM>, which interact with the bottom sash covering <NUM>. The sash profile seal <NUM> is shaped to fit the form of the glazing profile <NUM>. The length of the sash profile seal <NUM> is defined to at least cover a proportion of the area where the glazing profile <NUM> overlaps with the bottom sash covering <NUM>. In the assembled state the sash profile seal <NUM> can fill out the interspace between the glazing profile <NUM> and the bottom sash covering <NUM> and/or the glazing profile <NUM> and the side sash covering <NUM>. The bottom sash covering <NUM> here comprises an upstanding flange 154a provided with a cut-out <NUM> configured to receive the sash profile seal <NUM>. Details of the sash profile seal <NUM> may be found in Applicant's <CIT>.

On the side section <NUM>, an engagement pin 153a is provided and which is configured to interact with a key-hole shaped aperture (not shown) in a resilient flange on the side sash covering <NUM> to provide a snapping engagement which secures the side sash covering <NUM> to the sash in a manner known per se from Applicant's international publication <CIT>.

While the invention is primarily focused on improvements to the pane element <NUM> and the sash <NUM>, the embodiment shown in <FIG> provide for further improved tightness as well, at the frame <NUM>. Here a bottom frame gasket <NUM> is shown to interact with the bottom frame covering <NUM>. An end cap <NUM> is shown for providing a sealing at the bottom corners of the frame <NUM> The end cap member <NUM> is present in a left-hand and a mirror-inverted right-hand version.

Finally, and turning now to <FIG>, the side sash covering <NUM> in this embodiment has a slightly different shape compared to the above-described embodiments in that the end of the side sash covering <NUM> is formed with a separate cover cap 417b.

The roof window may for instance be manufactured by a method as follows:
A frame, a sash, and a set of cover members including a bottom sash covering are provided, having for instance a configuration substantially as described in the above.

During the process of preparing the exterior sheet, any solar control coating is optionally removed, for instance by etching, grinding, laser etc. Subsequently, the masking is applied. As mentioned, the masking may take any suitable form including a film, printing, enamel, ink. The masking is subjected to heat treatment, optionally during tempering.

The sheets of the pane elements are connected to each other, typically by means of spacers. In the case of two or more interior sheets, these sheets are first connected to each other, and an additional spacer is connected to the relevant interior sheet and to the exterior sheet to provide the assembled pane element, substantially as described in the above.

Subsequently, the pane element is connected to the sash such that the extended portion of the exterior sheet at least overlaps the bottom sash covering.

The roof window as described in the above is a sloping roof window configured to be installed in inclined roof surfaces forming an angle of about <NUM> to <NUM>° with the horizontal.

Claim 1:
A roof window (<NUM>) defining a length direction and a width direction and comprising
a frame (<NUM>),
a sash (<NUM>),
a pane element (<NUM>) comprising at least one interior sheet (<NUM>, <NUM>) and an exterior sheet (<NUM>), said pane element (<NUM>) being connected to the sash (<NUM>) by means of a glazing profile (<NUM>) extending in the length direction of the roof window at each side of the pane element (<NUM>), and
a set of cover members including a bottom sash covering (<NUM>) extending in the width direction of the roof window and a side sash covering (<NUM>) extending in the length direction of the roof window and connected to the sash (<NUM>) to extend over at least the glazing profile (<NUM>) and optionally the pane element (<NUM>) at each side of the pane element (<NUM>), the sash (<NUM>) being pivotally connected to the frame (<NUM>) by means of a set of hinges (<NUM>) defining a hinge axis (α) located between a top and a bottom of the roof window (<NUM>),
characterised in that
the exterior sheet (<NUM>) of the pane element (<NUM>) is provided with an extended portion (43b) extending beyond an inner portion (43a) to an edge (43c) at a distance from an edge (<NUM>) of the at least one interior sheet (<NUM>, <NUM>) and overlapping the bottom sash covering (<NUM>), the extended portion (43b) having such a configuration and such dimensions that its projection shadows the underlying bottom sash covering (<NUM>) and any other subjacent components, to at least a large extent, that at least one masking (<NUM>; <NUM>: <NUM>) is provided to substantially cover the extended portion (43b), and that each glazing profile (<NUM>) and each side sash covering (<NUM>) has such a length that they extend substantially to the edge (43c) of the extended portion (43b) of the exterior sheet (<NUM>) of the pane element (<NUM>).