Patent Description:
In recent years, the interest in energy-balanced buildings has increased and several attempts have been made to provide houses in which the energy for heating, cooling, water for domestic use etc. is provided solely by the surroundings.

One area of focus is the windows of the building, since one of the primary functions in a window, besides admitting light, is to allow stale, warm, or otherwise used or spent air inside the building (so-called "room air") to exit and allowing fresh air from the exterior ("outdoor air") to enter the building in which the window is installed. This presupposes that the window is openable. Over time, the provision of ventilation in windows, also in situations in which the window is not open, either because it is a fixed window, or simply is not open, has become more or less standard equipment. This is the result of, among other things, increased focus on improving indoor climatic conditions and the microclimate in buildings. One example of a roof window providing a ventilating aperture is the well-known VELUX® with a ventilation flap, which in pivot-hung windows also fulfils the double function of operating the window.

Natural ventilation provided by such a ventilation device has a number of advantages. Among others, it is free of charge and noise-less. However, in certain fields of applications, for instance mechanical ventilation may be desirable. Examples of prior art roof window systems, including roof windows and ventilation assemblies, are shown in for instance Applicant's European patents <CIT> and <CIT>, and in published Danish patent application <CIT>. Other examples are shown in documents <CIT>, <CIT>, <CIT> and <CIT>.

Although many of the above-mentioned prior art roof window systems, roof windows and ventilation assemblies provide well-functioning solutions, they also require that the roof window is built to receive such a ventilation assembly, typically by designing special parts and/or requiring further investment in the installation of auxiliary parts and installation equipment. Thus, severe limitations as to retro-fitting existing windows exist.

One recent development of such roof window systems is described in Applicant's European patent application published under <CIT>. Here, the ventilation assembly takes in outdoor air via ventilation units having flow channels connected to the ventilation device of the roof window and, conversely, allows room air to be led to the exterior in the form of exhaust air through the ventilation assembly. In one embodiment, the ventilation units comprise a ventilator and a heat exchange device in the form of a regenerator. The counterpart commercial product has proven to work well, and the roof window system alleviates the disadvantages of the earlier prior art to a great extent. One document devising further improvements of the above EP application is found in <CIT>.

Although both of these documents devise well-functioning roof window systems, there is an ongoing aspiration to improve the product itself, with an ever-increasing focus on improving the ventilation properties. Furthermore, challenges as to retrofitting still exist, since the construction of the relevant parts of the roof window depends on the functionality. For instance, a top-hung roof window has a more complex configuration at the top, i.e. at the typical connection point for the ventilation assembly. Similarly, an electrically operated roof window requires space for accommodation of operating equipment at the typical interfaces with the ventilation assembly.

With this background, it is therefore an object of the present invention to provide a roof window system, which provides for an improved connection between the roof window and the ventilation assembly, irrespective of the functionality of the roof window, and which at the same time provides for increased insulation and overall improved environmental conditions.

In a first aspect, this and further objects are achieved with a roof window system of the kind mentioned in the introduction, having the features of claim <NUM>.

Thereby a roof window system is provided in which the ventilation assembly may be connected directly to the exterior and/or to another ventilation assembly connected to the ventilation device of the roof window. In this way, additional ventilation is provided in a simple manner.

The first ventilation assembly includes a housing accommodating at least one ventilation unit connected to an aperture for air intake and exhaust, transition means being provided between the first ventilation assembly and the frame top member and the sash top member of the roof window to accommodate a set of flow paths for air to and from the ventilation assembly, said transition means comprise a plurality of apertures extending through the frame top member. Thereby, a roof window system is provided in which the transition between the two components of the roof window system, i.e. the roof window and the ventilation assembly, is carried out at a position which is as neutral as possible, that is, rather than leading the flow paths above the top frame member as in the prior art, the frame may accommodate other equipment as well, for instance a top hinge device. Furthermore, guiding the air through the frame top member also entails improved insulation properties, as the flow paths will extend through an area with better insulation.

In a second aspect, a method of providing ventilation according to claim <NUM> is provided.

Further presently preferred embodiments and further advantages will be apparent from the following detailed description and the appended dependent claims.

The invention will be described in more detail below by means of a non-limiting example of an embodiment and with reference to the schematic drawing, in which.

Referring first to <FIG> showing the overall appearance and principles underlying a roof window system in an embodiment wherein the roof window system comprises a roof window <NUM> and a single ventilation assembly generally designated <NUM>, the embodiment therefore not being according to the claimed invention.

The roof window <NUM> comprises at least one frame, in the embodiment shown and described two frames, of which one frame <NUM> is a stationary frame and an openable sash <NUM> encasing a pane <NUM>. Details of the frame <NUM> and sash <NUM> are shown in more detail in i. <FIG> and <FIG>. The frame <NUM> is, in a manner known per se, substantially rectangular and has a top member <NUM>, and further a bottom member <NUM>, and two side members, not shown in detail. The sash <NUM> has a top member <NUM> and two side members <NUM>, <NUM>, and further a bottom member, not shown in detail.

The frame <NUM> is adapted to be built into a roof structure of virtually any kind, typically comprising a number of rafters and battens, and further non-shown details such as vapour barrier collars etc., below a roofing material constituting a roofing <NUM> as shown in <FIG>.

Referring now further to <FIG>, an embodiment of the roof window system is shown installed in an upstairs room <NUM> of a multi-storey building. Above the room <NUM>, an attic <NUM> is present; however, this could also be a further inhabited storey, or a loft. Below the room <NUM>, a downstairs room <NUM> is present. In a typical situation, the downstairs storey is the first, or ground, floor of a house, the room <NUM> located upstairs being thus located on the second floor of the house.

As shown, the frame <NUM> is built into the roof structure such that the frame plane is substantially parallel to roofing <NUM>. The transition to the room <NUM> in the upstairs storey is here provided in that a set of lining panels comprising a top lining panel 73a, two side lining panels of which one side lining panel 73b is shown, and a bottom lining panel 73c, adjoins an inclined inner wall <NUM> of the upstairs room <NUM>. At the frame bottom member <NUM>, the bottom lining panel 73c is here shown connected to a window sill <NUM> and further to a knee wall <NUM> closest to a floor 77b of the upstairs storey, i.e. typically the second floor of a house. Alternatively, a different bottom lining panel could extend directly from the frame <NUM> to the floor 77b.

Opposite the floor 77b, the upstairs room <NUM> has a ceiling 76a which in turn adjoins the storey partition to the attic <NUM>, here shown with a floor 76b and an inner wall <NUM>.

The floor 77b of the upstairs room adjoins the storey partition to the downstairs storey and hence to downstairs room <NUM>, having a ceiling 77a and an inner wall <NUM> which is typically vertical.

Finally, a roof void <NUM> is shown formed behind the knee wall <NUM>. The roof void <NUM> typically unused space, but may be utilised for piping, wiring and additional insulation, and alternatively or additionally also for storage.

In the embodiment shown, the roof window <NUM> is centre-hung in that the sash <NUM> is connected to the frame <NUM> by a pivot hinge (not shown) provided between side members of the frame <NUM> and sash <NUM>, respectively, to be openable by tilting the sash <NUM> of the window <NUM> about a pivot hinge axis defined by the pivot hinge. As used in this description, a closed position of the roof window <NUM> means a position in which the frame plane and the sash plane coincide, that is form an angle of <NUM> degrees with each other. Similarly, an open position of the roof window <NUM> as used herein generally means a position in which the sash <NUM> is tilted about the pivot hinge axis such that the frame plane and the sash plane no longer coincide. Notwithstanding the centre-hung roof window described, the window of the system according to the invention may in other embodiments be top-hung, with or without an intermediate frame structure, have the hinge axis somewhere between the top and the centre, be side-hung or for that matter even be bottom-hung, or fixed, i.e. not openable. As will be described in further detail below, the roof window system also provides for optional ventilation in the closed position of the window. Furthermore, the window may be electrically operated, or prepared for retrofitting of an electrical operator. Finally, the roof window system comprises a screening arrangement <NUM> in the form of a roller shutter, in the embodiment shown.

The sash <NUM> and frame <NUM> of the window of the system according to the invention may be made of wooden members or members made of cast or extruded polyurethane (PUR). In the installed position, the frame <NUM> and sash <NUM> are protected, in a manner known per se, by an assembly of cover elements generally designated <NUM> and including a cladding and a flashing arrangement. Towards the interior, a suitable finishing may be provided, for instance comprising a lining panel. In the embodiment shown, the interior side of the sash members are substantially flush with the interior side of the frame members.

Furthermore, the frame bottom member <NUM> may be provided with an over-height, that is, taller than is necessary in order to surround the sash <NUM>, which in turn makes it possible to utilise standard flashing members at the bottom, even if the roof window <NUM> is installed at a deep position in the roof structure.

The roof window <NUM> of the system of the invention forms part of a roof window system which in addition to the roof window <NUM> comprises a ventilation assembly generally designated <NUM>. In the embodiment shown, the ventilation assembly <NUM> is positioned above the top member of the window frame <NUM> as seen in the inclination of the roof.

In the roof window system in the embodiment of <FIG>, the roof window <NUM> is installed to provide light and ventilation in the room <NUM> located upstairs in the multi-storey building, namely a room adjacent or at least in proximity to the inclined roof. As will be described in further detail below, the ventilation assembly <NUM> at the frame top member <NUM> is in fluid connection with a ventilation device of the roof window <NUM>, here generally designated <NUM>.

Referring now also to <FIG> and <FIG>, the ventilation device in the embodiment shown comprises a ventilation flap <NUM>, which is connected to the top member <NUM> of the sash <NUM> via a hinge connection <NUM> and which furthermore comprises a handle <NUM>.

Operating the handle <NUM> rotates the ventilation flap <NUM> from an open position to a closed position and vice versa. One or more intermediate positions, in which the ventilation flap <NUM> may be temporarily locked, may be defined between the open and closed position. In the embodiment shown and described, the sash <NUM> is pivotally connected to the frame <NUM>, and the ventilation flap <NUM> is adapted to assume three position, viz. a first or closed position, in which the roof window <NUM> is closed and no ventilation is provided, a second and ventilating position, in which the roof window <NUM> is still closed but a ventilation aperture is provided to allow air passage, and a third and entirely open position, in which the sash <NUM> is able to pivot relative to the frame <NUM> to open the window. In other windows, for instance a top-hung roof window, the ventilation flap <NUM> may be able to assume only two position, viz. a closed position and an open, ventilating position, whereas operation of the sash takes place in other ways, for instance by a handle or other operating means located at the bottom member of the sash.

Details of one embodiment of the ventilation assembly <NUM> will now be described in further detail with reference to in particular <FIG>. For the general operating principles underlying the ventilation assembly, reference is made to the above-mentioned <CIT>. The reference includes also ventilation units with ventilators and regenerators accommodated in the ventilation assembly.

The ventilation assembly <NUM> comprises a housing <NUM> and a cover <NUM>. The cover <NUM> has two apertures <NUM> for air intake and exhaust, the apertures <NUM> being provided at mutually opposite sides of the cover <NUM>.

Transition means provided between the ventilation assembly <NUM> and the top frame member <NUM> and the sash top member <NUM> of the roof window <NUM> of the system according to the invention will now be described in some detail. As in the prior art, these transition means are configured to accommodate a set of flow paths to and from the ventilation assembly <NUM>.

In the embodiment shown, the housing <NUM> of the ventilation assembly <NUM> is composed of three main components, namely in the form of a plurality of sections including a bottom section <NUM>, an intermediate section <NUM> and a top section <NUM>. Each of these sections is made of an insulating material. The material is preferably easy to manufacture and handle during assembly. It is also advantageous that the material is light-weight. In any event, the material should be able to withstand compressional and tensional forces to a certain extent and furthermore be able to provide the tightness required in such a ventilation assembly. One example is expanded polypropylene (EPP).

The top section <NUM> functions as a cover to the bottom section <NUM>, and is configured to accommodate internal parts of the ventilation units, cf. <FIG> and <FIG>. As is apparent, the bottom section <NUM> has a depth which exceeds that of the roof window <NUM>, i.e. the bottom section <NUM> is located deep in the roof structure which is advantageous from an insulation point of view.

The bottom section <NUM> is provided with a number of recesses or depressed portions, of which flow channel <NUM> is shown in <FIG> to represent the set of flow channels present in the housing <NUM> of the ventilation assembly <NUM> to form a fluid connection with the flow paths through the transition means.

At the front, or left-hand end of <FIG>, the bottom section <NUM> has an entrance portion 161a, which together with the underside of the intermediate section <NUM> forms an opening constituting a transition channel <NUM> to the roof window <NUM>. As shown, there are three other entrance portions corresponding to entrance portion 161a, which in turn provides for four transition channels <NUM>, <NUM>, <NUM>, <NUM>. All of these transition channels thus form part of the transition means between the ventilation assembly <NUM> and the roof window <NUM> and are here formed integrally in the housing <NUM> of the ventilation assembly <NUM>.

In the mounted condition, the transition channels <NUM>, <NUM>, <NUM>, <NUM> are in direct connection with apertures <NUM>, <NUM>, <NUM>, <NUM> in the frame top member <NUM> (cf. The bottom section <NUM> and the intermediate section <NUM> abut directly on the outer side of the frame top member <NUM> such that a substantially tight transition is achieved for the air flowing between the room in which the roof window is mounted and the ventilation assembly and vice versa.

Referring now also to <FIG>, with particular reference to <FIG>, another feature of the system of the invention will be described, which feature enhances the climate provided by the roof window system even further. Here, the transition means comprise a filter assembly as follows: A filter rail <NUM> is accommodated in the entrance portion 161a in the bottom section <NUM> of the housing <NUM>. The filter rail <NUM> is preferably releasably connected to the housing <NUM>. In the embodiment shown, the releasable connection is carried out in that a flange <NUM> on the filter rail <NUM> rests on shoulder portion 161b of bottom section <NUM>. The filter rail <NUM> is provided with lower guide <NUM> and upper guide <NUM>, which form a track to receive a filter holder <NUM> by a leg <NUM> thereof. The filter holder <NUM> has an opening <NUM> through which air flows and a surrounding flange <NUM> to abut on a ventilation rack <NUM> accommodated in the top sash member <NUM> as will be described in the following, and furthermore accommodates a filter element <NUM>. The filter holder <NUM> and the remaining three filter holders, which may be identical to the filter holder <NUM>, are received in the apertures <NUM>-<NUM> of the frame top member <NUM>. For reasons of clearness in the reading of the drawings, the filter holder <NUM> located in the aperture <NUM> is shown without a filter element, whereas the filter element <NUM> shown in aperture <NUM> is shown without its filter holder. The provision of a filter assembly contributes to an improved interior climate in the building. The filter elements may easily be cleaned or exchanged on a regular basis in order to maintain the indoor climate at a high level.

A central feature of the system of the invention emanates from in particular <FIG>, namely that the transition means between the roof window <NUM> and the ventilation assembly <NUM>, in the embodiment shown represented by filter holder <NUM> accommodated in aperture <NUM>, are located in the bottom part of the frame top member <NUM>. Preferably, the apertures <NUM>, <NUM>, <NUM>, <NUM> extending through the frame top member <NUM> are located mainly in the bottom half part of the height of the frame top member <NUM>, more preferably in the lower third part of the height of the frame top member <NUM>. Additionally, or alternatively, the apertures in the frame top member are located below, in the height direction of the frame top member <NUM>, internal equipment located at the top of the roof window, such internal equipment selected from the list comprising at least one of: a top hinge device, electrical operator means, a covering assembly, and a screening arrangement. Such internal equipment is generally designated <NUM> in <FIG>; the screening arrangement <NUM> is shown in <FIG> but has been removed from the detailed view of <FIG> for ease of readability. The relative positioning of the internal equipment, which does not require insulation, on one hand, and the apertures through which air will be transferred, entails an improved overall energy performance of the roof window system.

With reference to <FIG>, a further aspect of the system of the present invention will be described in detail. Here, it is shown how the ventilation rack generally designated <NUM> comprises a plurality of rack sections. Four rack sections are dedicated to ventilation, i.e. to provide a flow path for air to and from the ventilation assembly <NUM>. This applies to a first rack section <NUM> with aperture <NUM>, second rack section <NUM> with aperture <NUM>, third rack section <NUM> with aperture <NUM> and fourth rack section <NUM> with aperture <NUM>. In the embodiment shown, there are two rack sections dedicated to ventilation on either side to correspond with, i.e. form a fluid connection with, apertures <NUM>, <NUM>, <NUM>, <NUM> in the frame top member <NUM>. Furthermore, said plurality of rack sections here comprise a fifth rack section <NUM> with an aperture <NUM> configured to receive locking means (not shown) and a sixth rack section <NUM> with an aperture <NUM> configured to accommodate operating means of an electrical operator. Seventh and eighth rack sections <NUM> and <NUM> correspond to sixth and fifth rack sections <NUM> and <NUM>, respectively. In the embodiment shown, the rack sections <NUM>-<NUM> are positioned symmetrically about a central rack section <NUM>, but other configurations are conceivable. At the ends of the ventilation rack <NUM>, an end rack piece <NUM>, <NUM> is provided. In the exploded view of <FIG> one half of the ventilation rack <NUM> of <FIG> is shown, including two rack bridge pieces <NUM> and <NUM>. By the modular configuration of the ventilation rack <NUM> described in the above, a few standardised rack sections may be combined to fit any window size and functionality. In turn, this means that a more efficient employment of resources is obtained. In order to prepare the roof window <NUM> of the roof window system to retrofitting of accessories such as for instance an electrical operator or a screening arrangement, the set of standardised rack sections may also include sections with blind or knock-out plates to be removed in order to accommodate equipment of such accessories. The ventilation rack <NUM>, and in the embodiment shown, the rack sections, may be manufactured in any suitable way and from any suitable material, for instance moulding of a plastic material.

Moreover, a further and presently preferred aspect of the system of the invention will be described with particular reference to <FIG>. In a manner known per se the frame top member <NUM> is provided with a frame gasket <NUM> (frame top member <NUM> removed in <FIG>, frame gasket <NUM> thus shown in a "loose" connection). Together with other sealing elements along the side and bottom of the roof window <NUM>, this frame gasket <NUM> forms a first, or exterior, sealing plane. Towards the interior, a sash gasket <NUM>, correspondingly with other sealing elements, forms a second, or interior, sealing plane. In the embodiment shown, the sash gasket <NUM> is received in a track <NUM> in the ventilation rack <NUM>. To this end, the respective rack sections are provided with track portions (not shown in detail) to form the coherent, through track <NUM>. A plurality of brush seals <NUM>, <NUM>, <NUM> are connected to the central rack section <NUM> and the end rack pieces <NUM>, <NUM>, respectively. Together with the frame gasket <NUM> and the sash gasket <NUM>, the brush seals <NUM>, <NUM>, <NUM> form one or more closed chambers at the intersection between the frame <NUM> and the sash <NUM>, here two closed chambers on either side of the central rack section <NUM>. As a consequence, two flow channels between the roof window <NUM> and the ventilation assembly <NUM> pass in each of these closed chambers. The presence of such closed chambers are advantageous from a flow and insulation point of view, which in turn contributes to the improved environmental conditions.

Finally, and referring now to <FIG>, an embodiment of the roof window system according to the invention will be described.

As in the embodiments described in the above, the roof window <NUM> is connected to the ventilation assembly <NUM> at the top member <NUM> of the window frame <NUM>. The ventilation assembly <NUM>, in the following referred to as first ventilation assembly <NUM>, will provide ventilation to the upstairs room <NUM> as described. An additional, second ventilation assembly <NUM> is provided at the frame bottom member <NUM>. The second ventilation assembly <NUM> is in fluid connection with the downstairs room <NUM> by means of a duct <NUM> and a second ventilation device, here in the form of ceiling ventilation device <NUM> mounted in the ceiling 77a of the downstairs room <NUM>. As shown, the second ventilation assembly <NUM> and the duct <NUM> are accommodated in the roof void <NUM>. Although the duct <NUM> is here shown as a vertical element extending directly to the ceiling ventilation device <NUM> in the downstairs room <NUM> immediately below the upstairs room <NUM>, it is conceivable to provide additional ducting distributing air to and from other downstairs rooms, either on the same floor or in other storeys of the building.

The second ventilation assembly <NUM> is preferably provided in fluid connection with the first ventilation assembly <NUM>. The fluid connection is not shown in detail, but may for instance be provided in the form of ducts located along the side members of frame <NUM> as will be apparent to the person skilled in the art. In this way, the first ventilation assembly <NUM> provides for the air intake and exhaust, and possibly regeneration as described in the above, and the second ventilation assembly <NUM> may then be of a simpler design, providing only transfer of fresh air from the exterior to the downstairs room <NUM> and of stale air from the room <NUM> to the exterior via the first ventilation assembly. Alternatively, or additionally, the second ventilation assembly <NUM> is connected directly to the exterior, and not necessarily to the first ventilation assembly <NUM>. In fact, according to the invention, the second ventilation assembly (<NUM>) provides fresh air from the exterior. Intake of fresh air from the outdoors may for instance be provided in the form of apertures in the cladding and covering elements allowing entry and exit of air, but not precipitation, and the second ventilation assembly <NUM> is then preferably self-contained in that one or more ventilation units are provided within the second ventilation assembly <NUM> to enable mechanical ventilation.

By connecting the second ventilation assembly <NUM> to the downstairs room <NUM>, it is possible to utilise the aperture in the roof surface, which is traditionally only covered by the roof window <NUM>, as a gateway to mechanical ventilation of rooms on the ground floor (or lower floors), in addition to the room that the roof window <NUM> is located in.

Furthermore, the roof window system including a first ventilation assembly <NUM> and a second ventilation assembly may be used as a simple, decentralised system to transfer heat from a room or rooms on one storey of a building to another. In addition to providing air exchange as described in the above, one example could be that heated air accumulating under the ceiling 77a of the downstairs room <NUM>, resulting from a stove, fireplace or another heat source, could be used for transferring the heated air via the second ventilation device <NUM> to the ventilation device <NUM> of the roof window <NUM>, thereby heating the second floor room <NUM>.

Claim 1:
A roof window system comprising:
a roof window (<NUM>) having a frame (<NUM>) including a frame top member (<NUM>), two side members and a bottom member (<NUM>), defining a frame plane, and a sash (<NUM>) including a sash top member (<NUM>), sash side members (<NUM>) and a bottom member, and a pane (<NUM>), the roof window (<NUM>) further comprising at least one ventilation device (<NUM>) adapted for providing ventilation of a building in which the roof window is mounted,
at least one ventilation assembly (<NUM>, <NUM>) including a housing (<NUM>) accommodating at least one ventilation unit connected to an aperture (<NUM>) for air intake and exhaust,
transition means being provided between said at least one first ventilation assembly (<NUM>) and the frame top member (<NUM>) and the sash top member (<NUM>) of the roof window (<NUM>) to accommodate a set of flow paths for air to and from the first ventilation assembly (<NUM>),
characterised in that
said transition means comprise between said at least first ventilation assembly (<NUM>) and the sash top member (<NUM>) a plurality of apertures (<NUM>, <NUM>, <NUM>, <NUM>) extending through the frame top member (<NUM>),
wherein a second ventilation assembly (<NUM>) is provided at the frame bottom member (<NUM>) in addition to the first ventilation assembly (<NUM>) provided at the frame top member (<NUM>) of the roof window (<NUM>),
wherein the second ventilation assembly (<NUM>) provides fresh air from the exterior.