Abstract:
The invention relates to a mechanism for converting a rotary motion originating from a rotary energy generator ( 1 ) into a longitudinal motion of a carriage ( 25 ) that is adapted for attachment to a covering, such that said rotary motion will result in a longitudinal displacement of the covering, the mechanism comprising one or more spindle sections ( 2, 3, 4, 5 ) drivingly connected at a longitudinal end of at least one of said spindle sections via a gear means ( 7; 9; 22, 23, 24, 27 ) to said rotary energy generator ( 1 ). The invention further relates to a drive system for coverings comprising mechanisms according to the invention. The invention further relates to a covering system for covering a surface portion such as a window, glass door or the like, of a building.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to coverings for a surface portion of buildings, such as for windows. More specifically, according to one aspect, the invention relates to a drive system for such coverings that can be adapted to varying needs for instance related to varying physical characteristics of coverings or to varying modes of displacements of coverings relative to a building surface. The invention furthermore relates to coverings for building apertures that are provided with means for co-operation with the mechanisms and systems of the invention. According to further aspects, the invention relates to further improvements of coverings for surface portion of buildings, such as windows or glass doors or other forms of closable apertures of buildings. 
       BACKGROUND OF THE INVENTION 
       [0002]    Coverings for surface portions of buildings, such as for windows or similar closed apertures or transparent surface portions of buildings, that can be displaced between a position where the covering covers the surface portion and a position where the surface portion is either partially or fully uncovered are known within the art. The coverings are in practice positioned on a suitable drive and guide system that allows the desired displacement of the covering and that is provided with drive means for effecting this displacement. The drive and guide system must necessarily be placed outside on the surface of a building and be driven by suitable means such as one or more electric motors. Such motors are typically located in the drive and guide system, i.e. outside the building and this can cause problems in practice, for instance when a motor has to be dismantled for repair or replacement. 
         [0003]    Furthermore, known drive and guide systems displace the covering by drive means acting at a single point or at a single edge portion of a covering, for instance acting on the upper edge portion of a rectangular or quadratic covering. If the covering has sufficient rigidity this means of displacement of the covering may be satisfactory, but for a more light-weight and less rigid covering it may prove necessary to drive the covering at more than one locations for instance on the upper and lower edge portions of the covering. 
         [0004]    There is hence a need for a drive mechanism and drive system for coverings that allow high flexibility as regards placement of the motor, e.g. by providing a drive and guide system placed outside a building to be driven by one or more motors inside the building and for a mechanism and system that allows driving of the covering at more points or portions of the covering simultaneously, even by means of a single drive motor. 
       DISCLOSURE OF THE INVENTION 
       [0005]    On this background it is an object of at least some embodiments of the invention to provide drive mechanisms and systems that allow externally located guide and drive systems for coverings to be driven by one or more motors that may e.g. be placed inside a building 
         [0006]    It is a further object of at least some embodiments of the invention to provide drive mechanisms and systems that facilitate driving the covering at more than a single point or portion of the covering, preferably, although not necessarily, by a single drive motor. 
         [0007]    It is a further object of at least some embodiments of the present invention to provide drive mechanisms and systems that offer a high degree of freedom in design and implementation, e.g. horizontally or vertically. 
         [0008]    It is a specific object of at least some embodiments of the invention to provide a drive system that can be adapted to varying needs for instance related to varying physical characteristics of coverings or to varying modes of displacements of coverings relative to a building surface. 
         [0009]    It is a further object of at least some embodiments of the invention to provide a covering that facilitates the saving of energy. 
         [0010]    It is a further object of at least some embodiments of the invention to provide a covering that provides adequate protection against one or more environmental factors such as rain, heat, cold, sunlight, and/or the like. 
         [0011]    At least some of these and other objects and advantages are achieved by a drive mechanism according to the invention and a corresponding system comprising one or more such drive mechanisms according to the present invention. 
         [0012]    According to a first aspect, the present invention thus relates to a mechanism for converting a rotary motion originating from a rotary energy generator, such as an electric motor, into a longitudinal motion of a carriage that is adapted for attachment to a covering, such that said rotary motion will result in a longitudinal displacement of the covering, the mechanism comprising one or more spindle sections drivingly connected to said rotary energy generator at a longitudinal end of at least one of said spindle sections, e.g. via a gear means. 
         [0013]    According to an embodiment of the mechanism of the invention mechanism comprises a gear means for drivingly connecting one or more spindle sections to the rotary energy generator. In some embodiments, the gear means is an angular gear means converting a rotational movement of a drive shaft having a first longitudinal axis X 1  into a rotational movement of a second shaft having a second longitudinal axis X 2 , where the axis X 1  and X 2  form an angle between each other. 
         [0014]    The angle may be any angle larger than 0° and smaller than 180°. According to a specific embodiment said angle is substantially 90 degrees. 
         [0015]    According to an embodiment of the invention the carriage is guided for longitudinal movement along said one or more spindle sections, the carriage being provided with engagement members formed for engagement with the threads of the spindle sections, such that a rotation of the spindle sections will result in a longitudinal displacement of the carriage along the spindle sections. 
         [0016]    According to an embodiment of the invention the gear means comprises a housing accommodating a first gear wheel for connection to a drive axle of said rotary energy generator (for instance an electric motor) and a second gear wheel in engagement with the first gear wheel, the second gear wheel being adapted for connection to a longitudinal end of a spindle section. 
         [0017]    According some embodiments, the gear means is enclosed within a housing, where the housing is provided with a track through which the engagement members can pass in the longitudinal direction of the spindle, thereby making it possible for the carriage to pass the housing of the gear mechanism. 
         [0018]    According to a second aspect the present invention relates to a drive system for coverings for a surface portion of a building, in particular an exterior surface portion. The system may comprise a mechanism as described above. 
         [0019]    The coverings may be in the form of panels, shutters or similar, generally flat, planar structures that are slidably arranged on a surface of a building, in particular an exterior surface of a building. The coverings may be arranged to be placed in front of a closable aperture such as a glass door or a window, for example, for the purpose of shading the aperture from the sun or for providing other protection. The surface portion to be covered may thus be a window, a glass door or another transparent surface portion of the building. Generally, such coverings define an enclosed space between the surface portion and the covering. When not in use, the covering may slide to a position away from the aperture. The covering may comprise a slidable frame defining an aperture, and one or more cover members attached to at least a portion of the frame for covering the aperture defined by the frame. Examples of cover members include plates or panes, sheets of textile or another suitable material, slats, etc. For example, the aperture defined by the frame may be chosen to correspond in shape in size to the aperture of the building to be covered. The aperture defined by the frame may be rectangular or have a different shape. The slidable frame may comprise two vertical side frame members defining lateral edges of the covering, and two horizontal frame members defining upper and lower edges of the frame. Each frame member is an elongated member, e.g. formed as an extruded profile. A first carriage may be attached to a first frame member of the frame, e.g. the upper horizontal frame member, and a second carriage may be attached to a second frame member of the frame, e.g. a lower horizontal frame member, opposite the first frame member such that the carriages may engage respective parallel spindles that are spaced apart from each other in the transverse direction, thus allowing the spindles to be arranged on respective sides of an aperture of a building. 
         [0020]    Hence, the first and second drive spindles may be arranged parallel with each other and displaced from each other in the transverse direction by a distance corresponding to (e.g. substantially equal to) the size of the frame defined between the first and second frame members. 
         [0021]    According to an embodiment of the invention the system only comprises a first drive spindle for displacing a covering over a surface portion of for instance a wall or a window aperture, the covering comprising a frame. This first drive spindle is driven as set out above and arranged for converting a rotary motion into a longitudinal motion of a carriage attached to a first frame member, e.g. an upper frame member, of the frame. A second frame member opposite the first frame member relative to the aperture defined by the frame may run in a suitable guide track to guide its displacement over the surface portion. It is, however, also possible to drive a covering at two opposite frame members, e.g. at an upper frame member and at a lower frame member, which may be advantageous, if the covering has not sufficient rigidity to ensure stable displacement of the covering over the given surface portion. In this case the first and second drive spindles may be driven by a single motor in operative connection with either the first or second drive spindle or, as set out below, the first and second drive spindles may be drivingly interconnected by an interconnecting drive shaft that may be driven by a motor, for instance via a suitable gear member. The drive shaft may be connected to the first and second spindle, e.g. to longitudinal ends of the respective drive spindles, via suitable gear mechanisms. Hence, both drive spindles may be driven in synchronism by a single motor. It will be appreciated that the drive spindles define the direction of longitudinal movement of the covering. The drive spindles may be arranged parallel to the plane defined by the frame. 
         [0022]    According to an embodiment of the invention the system only comprises an upper drive spindle for displacing a covering over a surface portion of for instance a wall or a window aperture. This upper drive spindle is driven as set out above. The lower edge of a covering may run in a suitable guide track to guide its displacement over the surface portion. It is, however, also possible to drive a covering both at the upper edge portion hereof and at the lower edge portion hereof, which may be advantageous, if the covering has not sufficient rigidity to ensure stable displacement of the covering over the given surface portion. In this case the upper and lower drive spindles may be driven by a single motor in operative connection with either the upper or lower drive spindle or, as set out below, the upper and lower drive spindles may be drivingly interconnected by a drive shaft that may be driven by a motor, for instance via a suitable gear member. 
         [0023]    According to an embodiment of the invention the system comprises an upper drive spindle comprising one or more spindle sections, and a lower drive spindle comprising one or more spindle sections, where the upper and lower drive spindles are drivingly connected via an interconnecting drive shaft connected to corresponding longitudinal ends of said upper and lower drive spindles via an angular gear mechanism. 
         [0024]    According to an embodiment of the invention the rotary energy generator is drivingly connected to the upper drive spindle. 
         [0025]    According to another embodiment of the invention the rotary energy generator is drivingly connected to the lower drive spindle. 
         [0026]    According to still another embodiment of the invention the rotary energy generator is drivingly connected to the interconnecting drive shaft. 
         [0027]    According to a specific embodiment the invention relates to a system comprising a guide track member for insertion between a surface portion of a building, or a window, and a covering, the guide track member being provided with a spindle track for accommodating the drive spindle and an adjacent guide track for accommodating and guiding the carriage, wherein the guide track member is attached to said surface portion and the covering is attached to said carriage that is displaceable accommodated in the adjacent track. The guide track member may be a frame member of a support frame attached to a surface portion of a building e.g. to a window frame or another exterior surface of a building. 
         [0028]    According to a further aspect, disclosed herein are embodiments of a system for covering a surface portion of a building, the system comprising a covering for covering a surface portion of a building, and a support frame for attachment to a surface portion of a building, wherein the covering comprises a slidable frame, the frame comprising a carriage adapted for longitudinal movement along a guide track; wherein the support frame comprises a guide track member provided with a guide track ( 32 ) for accommodating the carriage; wherein the support frame comprises a sealing member for sealing an interface between the support frame and the frame of the covering when the covering is positioned in a position in front of the support frame. 
         [0029]    In some embodiments, the system thus comprises a support frame for attachment to a surface portion of a building, e.g. to a window frame or along or surrounding the periphery of a window, between the surface portion and a covering, e g along a periphery of an aperture or transparent portion of the surface of the building. The support frame may comprise a sealing member on a surface of the support frame facing the covering. The sealing may e.g. be a brush seal or a rubber seal extending along the frame portion. To this end, the support frame may comprise a receiving channel extending along at least a portion of the support frame. 
         [0030]    The sealing member may be a strip gasket, a strip brush, or another form of strip seal having an attachment part and a sealing part, where the attachment part is configured to be inserted in the receiving channel. Hence, the space defined between the covering and the surface portion to be covered and surrounded by the support frame and the slidable frame may be sealed against humidity and temperature differences, thus contributing to an improved insulation of the building. 
         [0031]    The sealing part may form a lip or blade-like portion or a hollow sealing bag. In some embodiments the sealing part may comprise folding lines that extend in the longitudinal direction of the strip. The folding lines are adapted facilitate collapsing or folding of the sealing portion when the covering is moved in front of the sealing member and exerts pressure on the sealing member. 
         [0032]    The attachment part may be formed with a resilient snap-on member that engages an interior wall of the receiving channel or with a barbed periphery that frictionally engages the interior wall of the mounting channel for positionally fixing the seal member relative to the support frame. 
         [0033]    In some embodiments, the support frame may have the same shape and size as the slidable frame of the covering, e.g. rectangular or in the form of a polygon with at least two parallel sides. The support frame may be formed by frame members in the same fashion as the slidable frame. A first frame member and a second frame member, e.g. two parallel side frame members or two parallel horizontal frame members, of the support frame may be formed as and function as guide track members provided with respective guide tracks for a carriage that is attached to the slidable frame, e.g. to corresponding first and second edge portions of the slidable frame. This allows the slidable frame to slide into position covering the support frame, along a direction defined by the first and second frame members of the support frame. To this end, the frame members forming the guide track members may longitudinal extend beyond the frame away from the surface portion to be covered, so as to allow the slidable frame to slide into a position where it does not cover or only partially covers the support frame. As described above, one or both guide track members may comprise a spindle track accommodating a drive spindle for longitudinal moving the corresponding carriage. 
         [0034]    In some embodiments one or more of the further frame members of the support frame, different from the first and second frame members, may comprise a drive track for accommodating a drive shaft operationally connected to a motor and to one or both drive spindles, as described herein. 
         [0035]    Accordingly, in some embodiments the frame members forming the support frame are each formed as a guide track member, e.g. made from a suitable weather-resistant extrudable material. The frame members of the frame may comprise two tracks, a first track shaped and sized to accommodate a drive spindle or a drive shaft, and a second track shaped and sized to accommodate a carriage of the slidable frame, or to receive an attachment part of a seal member. To this end, the second track is provided with a longitudinally extending, lateral aperture or slit in the wall facing the slidable frame allowing at least a mounting part of the carriage to project out of the second track towards a slidable frame, or for receiving an attachment part of the sealing member. Furthermore, the first and second tracks may be separated by a dividing wall that has a longitudinally extending aperture or slit allowing engagement members of the carriage to project into the first track and to engage a drive spindle accommodated in the first track. 
         [0036]    A weather protecting sealing between the slidable frame and the support frame may thus be provided at the sides of the support frame not engaged by a carriage of the slidable frame. To this end suitable seal members may be mounted e.g. in the second track. Sealing along the sides engaged by a carriage may be provided by the carriage and/or by additional seal members, e.g. a brush seal on the side of the slidable and/or the support frame facing the corresponding other frame. 
         [0037]    If neither a carriage nor a seal member is required along one or more portions of the support frame, the lateral aperture or slit facing the slidable frame may be covered by a suitable strip of cover material that may have an attachment part to be received in the second track in a similar manner as the attachment part of a sealing member. The first track may further be shaped and sized so as to receive one or more gear mechanisms, e.g. angular gear mechanisms described herein. Accordingly, all sides of the support frame structure may be formed from the same type of frame members, e.g. frame members having the same profile. 
         [0038]    The first and second tracks may be provided by a single rail or profile. Alternatively, the first and second tracks may be provided by separate rails or profiles that are connected to each other during installation of the drive system. In one embodiment, the first track may be formed by a first profile. The system may comprise bearing members as described in more detail below that are inserted into the first or spindle track so as to form lateral dividing walls. The bearing members may have coupling parts adapted to provide an interlocking connection with the interior circumference of the first track. The bearing members may further comprise coupling parts adapted to be connected with a second and a third profile that together form the second or guide track track. This embodiment provides a simple manufacturing process as the drive spindle and the bearing members may be assembled and connected to the second and third profiles before the thus assembled drive system is laterally inserted into the spindle track. 
         [0039]    Embodiments of the drive spindle described herein are may be comprised of a plurality of spindle sections, which may be advantageous for instance during storage and transportation of the system and contributes to the modular nature of the system described herein that allows the assembly of different types of coverings from a relatively small number of components. In some embodiments, each spindle section may comprise coupling members at their respective longitudinal ends, e.g. adapted to engage in a mating connection with corresponding coupling members of other spindle sections of the drive spindle so as to connect two or more spindle sections in longitudinal extension from each other. Hence, different versions and sizes of the drive system may be manufactured from a single type of drive sections. The dive spindle may e.g. comprise a drive shaft surrounded by one or more tubular spindle sections adapted to rotate with the drive shaft. It is however understood that also drive spindles comprising only one single section are covered by the invention. The drive spindle, or alternatively given sections hereof, may be substantially rigid, but also flexible spindles could be used in the invention. Both types of spindles fall within the scope of the invention. 
         [0040]    Although in the following detailed description the drive spindle(s) are shown extending horizontally, and in some embodiments the interconnecting shaft driving both drive spindles in common are shown extending vertically, the reverse could also be the case, and generally, the drive mechanisms and systems of the invention can have any orientation other than horizontal/vertical. Even more generally, the present invention may also be used for coverings that are not rectangular or quadratic. For instance application of the mechanism and system according to the invention for a parallelogram-shaped covering would be possible. 
         [0041]    The dimensions and the design of the mechanism according to the invention can be such that they can form part of a window profile just as they can be mounted on an existing window or alternatively directly on a covering. 
         [0042]    The drive motor, control system and battery (for instance a stand-alone unit with a solar collector/panel or other, alternative energy supply) can either be placed internally in the building or externally on the system or be an integral part of guide track system of the mechanism. 
         [0043]    In some embodiments the drive system comprises one or more bearing members that may be distributed spaced apart from each other along the length of the drive spindle. The bearing members may fix the lateral position of the spindle within a spindle track, thus providing a smooth operation and reducing noise. For example the bearing members may be formed as laterially extending walls in the spindle track with an aperture for receiving the drive spindle. The bearing members may be provided at intervals corresponding to the length of the spindle sections, such that they are arranged at the positions where two spindle sections are connected to each other. In some embodiments the bearing members are formed as plates, e.g. made of plastic, that have an outer periphery matching the interior circumference of the spindle track and a central through hole through which the drive spindle may extend. The plates may e.g. be generally c-shaped allowing them to be snapped onto the drive spindle. 
         [0044]    According to a further aspect, disclosed herein are embodiments of a system for covering a surface portion of a building, the system comprising a covering for covering a surface portion of a building, and a support frame for attachment to a surface portion of a building, wherein the covering comprises a slidable frame, the frame comprising a carriage adapted for longitudinal movement along a guide track; wherein the support frame comprises a guide track member provided with a guide track for guiding the carriage; wherein the covering comprises one or more ventilation channels connecting the side of the covering facing the surface of a building and the side facing away from the building. 
         [0045]    Generally, a covering may be provided with one or more ventilation holes or channels providing a fluid path from the side of the covering facing the surface of a building and the side facing away from the building. This allows ventilation of the space between the covering and the surface of the building, e.g. a window, covered by the covering. The ventilation holes or channels may be provided in the cover material and/or in the slidable frame supporting the cover material. In some embodiments the ventilation channels are provided in the lower and/or upper frame members, thus allowing ventilation to be supported by convection of air being heated in the space between the covering and the surface of the building, e.g. by sunlight. This creates a chimney effect creating an upwardly directed stream of air. In some embodiments, the surface of the building covered by the covering may likewise comprise one or more ventilation apertures communicating between the interior of the building and the space between the outer surface of the building and the covering. Hence, a ventilation of the building may be provided even when the covering is closed. 
         [0046]    In some embodiments, the covering comprises a small turbine arranged in the ventilation stream of ventilation air, e.g. the upwardly directed stream of air in the space between the covering and the surface of the building. The turbine may be adapted to convert energy of the air stream into electrical energy. The turbine may e.g. be located in the ventilation channel of the lower and/or upper frame member. Alternatively, electrically driven fans may be provided to increase the ventilation effect. 
         [0047]    Specific and non-limiting embodiments of the various aspects are described in the detailed description of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0048]    The invention will be better understood by reading the following detailed description of non-limiting embodiments of the invention in conjunction with the figures, where: 
           [0049]      FIGS. 1(   a ) and ( b ) is a schematic representation of a drive system according to an embodiment of the invention showing upper and lower drive spindles laterally connected by a drive shaft and driven by a drive motor; 
           [0050]      FIG. 2  is a schematic view of a first configuration of a drive system according to the invention with the drive motor placed adjacent the upper drive spindle and with a guide track for a covering at the bottom of the configuration; 
           [0051]      FIG. 3  is a schematic view of a second configuration of a drive system according to the invention with the drive motor placed adjacent the upper drive spindle and where the drive system is further provided with a lower drive spindle placed for engagement with the lower part of a covering, and where the upper and lower drive spindles are drivingly connected via a laterally placed vertical drive shaft; 
           [0052]      FIG. 4  is a schematic view of a third configuration of a drive system according to the invention with the drive motor placed adjacent the connecting laterally placed drive shaft that drivingly connects the upper and lower drive spindles; 
           [0053]      FIGS. 5(   a ) and ( b ) is a schematic perspective view of the driving connection between the spindle and the drive shaft via an angular gear coupling, wherein is further shown a schematic representation of carriage provided with engagement means for coupling the spindle to a covering; 
           [0054]      FIG. 6  is a schematic representation of angular gear mechanism and spindle bearings according to an embodiment of the invention; 
           [0055]      FIG. 7  is a schematic perspective view of the connection between a window section in a building and the frame of a covering showing a drive profile comprising a longitudinal spindle track for accommodating the spindle and an adjacent longitudinal track for the carriage, which carriage is connected to the frame of a covering; 
           [0056]      FIG. 8  is a schematic representation of a guide track member and a drive spindle: 
           [0057]      FIG. 9  shows an example of a drive spindle comprising multiple spindle sections; 
           [0058]      FIG. 10  shows components of an example of a drive system; 
           [0059]      FIG. 11  shows an example of a covering system; 
           [0060]      FIG. 12  shows an example of a covering; 
           [0061]      FIGS. 13-15  show examples of covering systems with ventilation channels; 
           [0062]      FIG. 16  shows an example of a covering system with a ventilation channel comprising a turbine. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0063]    Referring to  FIGS. 1(   a ) and ( b ) there is shown a schematic representation of a drive system according to embodiments of the invention showing upper and lower drive spindles  11 ,  12  laterally connected by an interconnecting drive shaft  10 . In  FIG. 1(   a ) the upper drive spindle  11  is driven by a drive motor  1  in engagement with the spindle via an angular gear mechanism  7  as will be explained in detail below. The upper spindle can be comprised of a number of spindle-sections  1 ,  3 ,  4 ,  5 , but only a single such section may also be used according to the circumstances. In both of the embodiments shown in  FIGS. 1(   a ) and  1 ( b ) the upper drive spindle  11  is connected with a lower drive spindle  12  by means of a laterally located interconnecting drive shaft  10  connected at either longitudinal ends with the respective spindle sections via an angular gear mechanism  9 . If more than one spindle section is used in the upper and/or lower drive spindle, these sections can be interconnected as explained below. The drive system according to the invention makes it possible to connect the drive means such as the motor  1  at a convenient place in the system, according to the specific circumstances, and the use of more than one drive motor is also possible by simple means according to the invention. In  FIG. 1(   a ) the drive motor  1  is coupled to the drive system via the upper drive spindle  11  and in  FIG. 1(   b ) the drive motor is alternatively coupled to the drive system via the connecting shaft  10  and via a suitable angular gear member  9  connecting the interconnecting shaft  10  to the drive shaft  8  of the motor. Longitudinally distributed along the drive spindles  11  and  12  may be positioned spindle bearings  6  that support the spindle and hence facilitates a smooth rotation of the spindle with reduced noise. 
         [0064]    Referring to  FIG. 1(   b ) it is noted that although the two lower spindle sections are shown schematically with spindles having the same pitch direction as the two upper spindle sections this requires that in the angular gear member  9  the drive axle  8  of the motor  1  drives the two respective connecting shafts  10  on either side of the gear via separate gear wheels. If a gear member  9  of the kind shown for instance in  FIGS. 5(   b ) and  6  is used, opposite pitch directions of the upper and lower spindle sections must be used. 
         [0065]    As mentioned initially, the present invention facilitates the provision of drive systems of a number of alternative configurations, of which non-limiting examples are shown in  FIGS. 2 ,  3  and  4 . With reference to  FIG. 2  there is thus shown a schematic view of a first configuration of a drive system according to the invention with the drive motor  1  placed adjacent the upper drive spindle  11  and with a guide track  13  for supporting and guiding a covering (not shown) at the bottom of the configuration. 
         [0066]    With reference to  FIG. 3  there is shown a schematic view of a second configuration of a drive system according to the invention with the drive motor  1  placed adjacent the upper drive spindle  11  and where the drive system is further provided with a lower drive spindle  15  placed for engagement with the lower part of a covering (not shown), and where the upper and lower drive spindles  11 ,  15  are drivingly connected via a laterally placed vertical interconnecting drive shaft  14 . 
         [0067]    With reference to  FIG. 4  there is shown a schematic view of a third configuration of a drive system according to the invention with the drive motor  1  placed adjacent the connecting laterally placed drive shaft  16  that drivingly connects the upper and lower drive spindles  11 ,  15 . 
         [0068]    A further class of embodiments of the drive system according to the invention comprises laterally placed drive spindles at one or both lateral sides of the drive system and optionally connecting drive shafts connecting these spindles. As seen for instance in  FIG. 4 , this would correspond to the portions  12  and/or  16  being drive spindle portions and the portions  11  and/or  15  being connecting drive shafts. By these means a covering may be displaced vertically instead of horizontally, as is implicitly assumed in  FIGS. 2 ,  3  and  4 . 
         [0069]    In the following a detailed description of embodiments of means for connecting a drive motor to the system and for providing driving engagement between the drive system and a covering is shown. 
         [0070]    With reference to  FIG. 5(   b ) there is shown a schematic perspective view of the driving connection between the spindle  17 ,  20  and the drive shaft  21  of a drive motor via an angular gear coupling. The angular gear coupling comprises a first gear wheel  22  operatively connected to the drive shaft  21  of the motor and in driving engagement with a second gear wheel  23  that is operatively connected to the corresponding spindle portion. The angular gear mechanism is housed within a housing  24  that may also serve as a bearing for the spindle. In the housing  24  there is provided a longitudinally extending track allowing the carriage  25  to become longitudinally displaced in the direction of the spindle and past the gear housing  24  of the gear mechanism. In  FIG. 5  there is furthermore shown a schematic representation of a carriage  25  that is to be attached to a covering and which is provided with engagement means  26  for coupling the spindle to a covering. Preferably there are three such engagement means  26 , whereby at least two engagement means  26  are always in engagement with the spindle. The distance between the engagement means  26  corresponds to the pitch of the spindle. Generally, at least two engagement means may be spaced apart in the longitudinal direction further than the longitudinal extent of the housing of the gear mechanism, thus ensuring that always at least one of the engagement members is engaged with the spindle. 
         [0071]    In  FIG. 5(   b ) there is shown the same embodiment of the driving connection as in  FIG. 5(   a ), but viewed from above. The carriage  25  shown in  FIG. 5(   b ) is provided with three engagement means  26 , which as mentioned above is more preferable than the two engagement means shown in  FIG. 5(   a ). A track is provided in the housing  24  for making passage of the engagement means  26  past the drive connection possible. 
         [0072]    With reference to  FIG. 6  there is shown a schematic representation of a preferred embodiment of an angular gear mechanism and spindle bearings according to the invention. The housing  24  comprises openings  35  for the passage of spindle shaft portions  36  through the openings  35  and engagingly through the gear wheel  23  that is en driving engagement with the gear wheel  22  that is—or can be brought into—connection with the drive shaft  8  of a drive motor.  FIG. 6  clearly shows the track  27  provided in the housing  24  for making passage of engagement means of a carriage past the gear mechanism possible.  FIG. 6  also shows a bearing  28  for the spindle, which bearing is also provided with a track  27 ′ through which the engagement means can pass in the longitudinal direction of the spindle. 
         [0073]    It is understood that although the angular gear mechanisms shown and described throughout the detailed description of the invention are designed for a drive shaft extending substantially perpendicularly relative to the longitudinal axis through the spindle, other angles between the drive shaft and the spindle could also be used depending on the circumstances and that even a parallel extension of the drive shaft with the spindle would be possible within the scope of the present invention. 
         [0074]    With reference to  FIG. 7  there is shown a schematic perspective view of the connection between a window section—generally designated by reference numeral  34 —in a building and the frame  33  of a covering. The interconnection between the window portion and the frame of the covering comprises the guide track member  30 , for instance formed of an extruded metal or plastics profile, and comprising a longitudinal spindle track  31  for accommodating the spindle and an adjacent longitudinal track  32  for accommodating the carriage  25 , which carriage  25  is connected to the frame  33  of a covering. 
         [0075]      FIG. 8  is a schematic representation of a guide track member and a drive spindle. The guide track member comprises a first profile  38 , a spindle  20 , bearing plates  28 , and second profiles  43 . The first profile  38  defines a spindle track for accommodating the spindle  20 . The first profile  38  is u-shaped and the spindle track has a generally rectangular cross section. The side walls of the profile comprise grooves for receiving coupling members  40  of the bearing plates  28 . 
         [0076]    The spindle  20  is a tubular member having a central tube  44  for receiving a drive shaft  36  for driving the spindle. 
         [0077]    The bearing plates  28  have a central hole  41  for receiving a bushing  37  through which the shaft  36  may extend. The bearing plate has a circumferential shape that matches the interior circumferential shape of the profile  38 . The bearing plate further has coupling members  40  configured to engage the grooves  39  of the profile  38  when the bearing plate is inserted into the spindle track. 
         [0078]    Each bearing plate  28  further comprises coupling members  42  for connecting the bearing plate to profiles  43 , e.g. in a snap-op fashion such that the profiles  43  together define a guide track for the carriage of a covering. 
         [0079]    The drive system may thus be assembled by attaching the bearing plates  28  to the profiles  43 , inserting the bushings  37  in the holes  41  of the bearing plates, positioning the drive shaft sections  20  between adjacent bearing plates such that the central tube  44  of the drive shaft is aligned with the holes  41  of the bearing plates, and advancing the drive shaft  36  through the bushings  37  and the inner tube  44  of the spindle sections  20 . The resulting assembly may then be connected with the profile  38  by laterally inserting the spindle  20  and bearing plates  28  into the spindle track until the coupling elements  40  engage the grooves  39 . 
         [0080]      FIG. 9  shows an example of a drive spindle comprising multiple spindle sections. In particular,  FIG. 9   a  shows a spindle section  20  configured to be connected with other, like spindle sections so as to assemble a longer spindle made up of two or more such spindle sections. To this end, the spindle section  20  comprises respective coupling members  45  and  46  at its respective longitudinal ends. The coupling members are configured to engage in a mating connection with corresponding coupling members on another, like spindle section, e.g. in a resilient snap-on fashion. In the example of  FIG. 9   a , the spindle section comprises a male coupling member  45  at one end and a female coupling member  46  at the other end. The coupling members are arranged such that the spindle sections can only be coupled to each other in a predetermined angular relationship so as to cause the combined spindle to have continuous helical thread  17 . 
         [0081]      FIG. 9   b  shows in a partly sectional view of two spindle sections  20   a - b  connected to each other. At the connection the helical thread leaves a circumferentially extending gap for accommodating a bearing plate  28 . Hence, a male coupling member  45  of one spindle section  20   a  may be inserted into the hole of the bearing plate  28 , and the female coupling member of the other spindle section  20   b  may be connected to the coupling member  45  protruding through the hole of the bearing plate. As described above, the spindle sections have a central tube through which a drive shaft  36  may extend. 
         [0082]      FIG. 10  shows components of an example of a drive system. In particular,  FIG. 10  shows a support frame whose frame members/legs are formed by guide track members  30 . The guide track members comprise a spindle track for receiving either a spindle  20  or an interconnecting drive shaft  10  for connecting drive spindle  20  with a motor and/or another drive spindle. The guide tack members  30  further comprise an adjacent guide track  32  for receiving a carriage (not shown) of a covering or for receiving an attachment part of a sealing member (not shown). The drive spindle  20  may be of the type shown in  FIG. 9  comprising a plurality of spindle sections and supported by bearing plates  28  and a central drive shaft. The drive system of  FIG. 10  comprises a spindle extending in frame member of the support frame and an interconnecting shaft  10  extending in the adjoining frame member. The drive spindle and the interconnecting shaft  10  are coupled to each other by an angular gear mechanism  9  which is also accommodated in the spindle track of the support frame and located in a corner of the support frame. 
         [0083]      FIG. 11  shows an example of a covering system. In particular,  FIGS. 11   a - 11   b  show a sectional view of a covering system for a window of a building. The covering system comprises a support frame whose frame members are formed by guide track members  30  for supporting and driving a covering. The system further comprises a covering comprising a slidable frame  33  and a cover member  53 . In the example of  FIGS. 11   a - b,  the guide track member  30  is mounted to the window frame  54  of a window. The window further comprises a sash  55  and a window pane  56 . 
         [0084]    The guide track member  30  comprises a spindle track  31  and an adjacent guide track  32 , e.g. as described in connection with  FIGS. 7-10 . 
         [0085]      FIG. 11   a  shows the covering in closed position covering the window and where the slidable frame  33  is positioned in front of the support frame  30 , while  FIG. 11   b  shows the covering in a partly open position where the slidable frame  33  has been slid away sideways from the support frame  30  so as to partly expose the window. Hence,  FIGS. 11   a - b  show cross sections of those frame members of the slidable frame  33  that do not comprise a carriage engaging a drive spindle in the spindle track. Instead, a sealing member  48  is inserted in the guide track  32  of the support frame member  30  as indicted by a circle in  FIGS. 11   a - b  providing a weather seal between the support frame and the slidable frame, when the covering is in a closed position. 
         [0086]    The seal  49  may be a seal strip or gasket, e.g. made from rubber or another suitable material, having a sealing part  49 . In the example of FIGS.  11 - a - b,  the sealing part  49  is in the form of a collapsible, hollow structure which can be compressed to a collapsed state when the slidable frame is in its closed position in front of the support frame, as shown in  FIG. 11   a . When the slidable frame  33  is moved away from the support frame member  30 , the hollow sealing part  49  returns to an uncollapsed configuration, as shown in  FIG. 11   b . However, other forms of sealing members such as brush seals may be used instead. 
         [0087]      FIG. 11   c  shows a more detailed sectional view of a guide track member  30  of the support frame with a sealing strip inserted in the guide track  32 . The guide track member comprises a longitudinally extending spindle track  31  and adjacent, longitudinally extending guide track  32 . The two tracks are separated by a partial dividing wall which leaves a longitudinally extending aperture or slit between the tracks allowing engagement members of a carriage that moves in the guide track  32  to engage a spindle located in the spindle track  31 . The guide track  32  also has a longitudinally extending aperture  79  facing the slidable frame (not shown) allowing a carriage in the guide track  32  to be connected to a slidable frame. 
         [0088]    In the example of  FIG. 11   c,  a generally u-shaped profile  47 , e.g. made of plastic, is initially inserted into and fastened inside the guide track  32 , e.g. by a resilient snap-in mechanism. The profile  47  is inserted with its open end facing the lateral aperture  79  of the guide track  32  so as to provide a receiving channel of suitable size and shape for a sealing member  48 . 
         [0089]    The sealing member is a strip seal having an attachment part  51  and a sealing part  49 . The attachment part is configured for insertion into the receiving channel of the profile  47  and for fastening therein, e.g. by frictional or resilient engagement with the interior circumference of the receiving channel of the profile  47 . The sealing part  49  extends out of the receiving channel towards a slidable frame (not shown). In the example of  FIG. 11   c,  the sealing part  49  is a hollow structure having a generally triangular cross section, but where the exposed sides of the triangle have longitudinal folding lines  50  (e.g. longitudinally extending grooves) that facilitate collapsing or folding of the sealing part  49  upon exposure to pressure from a slidable frame being moved into a position in front of the guide track. 
         [0090]    It will be appreciated that the seal member  48  and the profile  47  may alternatively be provided as a single element such that the sealing member may be inserted directly into the guide track  32 . 
         [0091]      FIGS. 11   d - f  illustrate different examples of sealing members  48  comprising respective attachment parts  51  and sealing parts  49 . The sealing members of  FIGS. 11   d  and  e  are similar to the sealing member of  FIG. 11   c  in that their sealing parts  49  are hollow structures defined by relatively thin side walls. The sealing part  49  of  FIG. 11   d  has a symmetric cross section while the sealing part  49  of  FIG. 5   e  has an asymmetric cross section. Furthermore, the sealing part  49  of  FIG. 11   e  has an additional internal support wall  52  connecting a base wall of the hollow structure and one of its side walls. The side walls of the sealing part  49  of  FIG. 11   e,  and optionally the support wall  52 , are also provided with folding lines  50  as described above. 
         [0092]    The sealing part  49  of the sealing member  48  shown in  FIG. 11   f  has a blade-like shape. 
         [0093]      FIG. 12  shows an example of a slidable frame  33  and cover member  53  of a covering. The frame  33  is made from extruded profiles forming at least two channels  59 . A receiving channel  56  provides a lateral receiving slit for receiving the edges of the cover member  53 , e.g. a pane of suitable material or a sheet material mounted on a frame. A ventilation channel  58  is located adjacent to and on the mounting side of the receiving channel  56 , i.e. closer to support frame to which the slidable covering is to be mounted. The outer and inner side walls of the ventilation channel are provided with ventilation holes  60  and  61 , respectively so as to provide a ventilation path between the exterior of the covering and the space between the covering and the surface covered by the covering. Generally, it will be appreciated that the covering may comprise a mechanism for opening and closing the ventialation hols  60  and/or  61  or otherwise selectively blocking the ventilation path so as to control the ventilation manually and/or automatically. As will be described in greater detail below, the ventilation holes may be provided on some or all sides of the frame  33 . In some embodiments they are provided only in the upper and/or lower horizontal members of the frame. 
         [0094]    The frame  33  further comprises mounting means  62  for attaching a carriage to the frame  33 . In the example of  FIG. 12 , the mounting means  62  is formed as a lateral aperture facing the support frame and into which a mounting part of the carriage may be inserted and secured, e.g. by screws, e.g. extending through the upper and/or lower walls of the profile. 
         [0095]    The frame further comprises a receiving channel  57  facing the support frame for receiving a seal strip, e.g. a brush seal. 
         [0096]      FIG. 13  shows further examples of a covering system. Each of  FIGS. 13   a - c  shows a covering system similar to the system of  FIG. 11   a.  The system comprises a covering and a support frame  30  for supporting and driving the covering. The covering comprises a slidable frame  33  and a cover member  53 . The covering system is mounted to a window frame  54  of a window of a building, the window comprising the frame  54 , a sash  55  and a window pane  56 .  FIGS. 13   a - c  illustrate different embodiments of ventilation channels. 
         [0097]    In the embodiments of  FIGS. 13   a - b,  a ventilation channel is integrated in the slidable frame  33 , e.g. the lower and/or upper horizontal frame member, while in the embodiment of  FIG. 13   c , the ventilation channel  65  is provided in the cover member  53 . 
         [0098]    In the example of  FIG. 13   a , the inward portion of the frame member  33  comprises a number of holes  60  and  61 . In the example of  FIG. 13   b , the bottom member of the frame is formed by two separate profiles that leave a ventilation channel between them. The ventilation channel has an exterior inlet  63  and an outlet  64  proximal to the support frame. 
         [0099]      FIGS. 14-15  show examples of covering systems with ventilation channels allowing ventilation of the interior of the building even with the covering closed. Each of  FIGS. 14   a - e  and  FIGS. 15   a - d  shows a covering system similar to the system of  FIG. 11   a , comprising a support frame (not explicitly shown) and a covering including a slidable frame  33  and a cover member  53 . The covering system is mounted to a window frame  54  of a window of a building, the window comprising the frame  54 , a sash  55  and a window pane  56 . The window is mounted in an exterior wall  67  of a building. 
         [0100]    In the example of  FIG. 14   a , the slidable frame  33  comprises a ventilation channel  60  in the lower frame member of the frame  33 , and the slidable frame and/or support frame of the covering system is sufficiently wide so as to allow at least a part of the window  66  to be opened when the covering is closed. Hence, fresh air can enter the building through the ventilation channel  60  in the frame  33  and the open window  66 . 
         [0101]    In the example of  FIG. 14   b , the window comprises lower and upper ventilation openings  68  and  69 , respectively. Allowing air from the interior of the building to enter the space between the covering and the window though the lower opening  68  and to re-enter the interior of the building through the upper opening  69 , thus allowing utilisation of the thermal convection in the space between window and covering so as to utilise heat created by sunlight irradiating on the covering. 
         [0102]      FIGS. 14   c - e  illustrate how ventilation openings  70  at the top of a window can be combined with ventilation channels  60   a,    60   b  in the bottom and/or upper frame members of the slidable frame  33  so as to provide selective ventilation, e.g. to allow fresh air to enter through ventilation channels  60   a  at the bottom of the slidable frame, provide heating of the air in the space between window and covering, and to allow the heated air to enter the building through an opening  70  at the top of the window e.g. in the form of a small extra window. This opening  70  may be arranged inside the covering as in  FIG. 14   d ) or outside the covering (as in  FIG. 14   c ). By selectively opening or closing the ventilation channels  60   a  and  60   b  such a system may also be used to allow warm air to exit the building through an upper ventilation opening  70  of the window and ventilation channels  60   b  in the upper part of frame  33 , e.g. as illustrated in  FIG. 14   e.    
         [0103]      FIG. 15   a  shows another example similar to the one of  FIG. 14   c , but where the ventilation opening of the window is provided as a separate channel  74  above the frame  54 . 
         [0104]      FIGS. 15   b - c  show an example of the covering system where the window comprises one or more ventilation channels including a ventilation fan  75 ,  76  respectively. This facilitates a more efficient ventilation and a flexible and selective control of the ventilation, e.g. as regards the direction of the air stream. Electrical power for driving the fans may be generated by solar panels  80  on the exterior surface of the window or building Such solar panels may further be configured to charge a rechargeable battery so as to allow operation of the ventilation fans in the absence of sunlight. In yet further embodiments, the electrical power of the solar panels may be used for interior illumination  81 . 
         [0105]    The example of  FIG. 15   d  is similar to the one of  FIG. 14   d  but where the air enters the space between the covering and the window through holes in the cover member  53 . 
         [0106]      FIG. 16  shows an example of a covering system with a ventilation channel comprising a turbine. In the example of  FIG. 16 , the bottom frame member of the covering comprises ventilation channels in which a turbine is inserted such that the ventilation stream passes through and drives the turbine  77  so as to allow generation of electrical power. The ventilation stream and thus the power generation is facilitated due to convection in the space between the window pane  56  or other surface of the building and the cover member  53  due to heat generated by sunlight. It will be appreciated that this effect may be increased by suitable choice of materials and colors of the cover member and of the surface covered by the covering. It will further be appreciated that the turbine mat be located at an upper frame member or other suitable position in the ventilation stream.