Abstract:
A rotatable window pane assembly and method of repositioning the same is disclosed in which the window pane assembly comprising a frame and at least one window pane is rotatably supported in a fixed frame from a first position, such that the at least one window pane is parallel to an aperture defined by the fixed frame, to a second position, such that the at least one window pane is parallel to the aperture defined by the frame and a second surface of the at least one window pane faces the outside, or from a second to first position. A seal assembly comprising a seal frame and at least one pliable seal carried is located on the inside with respect to the fixed frame and is pivotally displaceable independently of the position of the window pane assembly, from a closed position in which the seal frame is parallel and adjacent to the aperture defined by the interior surface of the fixed frame to an open position in which the seal frame is spaced from and at an angle to the aperture.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to the field of fenestration. More particularly, the invention relates to a method and apparatus for rotating a waterproof window pane assembly 360 degrees with respect to a fixed frame, wherein the thermal and optical performance of the window pane assembly depends on the orientation of the glass surfaces contained therein. The rotatable window pane assembly also allows for improved accessibility to the exterior face of the glass surfaces of conventional windows to enable the cleaning thereof.  
       BACKGROUND OF THE INVENTION  
       [0002]     Glazed openings permit the flow of energy between an interior and an exterior by conduction, convection and radiation. Ordinary, nearly transparent, standard double-strength sheet glass allows about 87% of the solar radiation (ASHRAE (1989), 1989 Fundamentals Handbook, ASHRAE, Atlanta) to pass. The uncontrolled influx of solar energy through large glazed openings has numerous drawbacks, for example: 1) extreme overheating in the summer; and 2) visual discomforts of glare both in summer and in winter. Furthermore, direct sunlight has a deleterious effect on furniture and objects located near the opening.  
         [0003]     The traditional response to these problems has been to incorporate shading devices, which reduce the exposed area of the glazing.  
         [0004]     Fixed shading devices are generally installed on the exterior of the windows. Usually they do not require maintenance, but they cannot be adapted to changing meteorological conditions, and, while screening out direct solar radiation, have little effect on diffuse or reflected radiation.  
         [0005]     Operable shading devices on the exterior of windows are designed to allow control of the incoming radiation at all times. They may have complex mechanisms which require maintenance or replacement, and require either user intervention to operate properly, or expensive automatic control systems.  
         [0006]     The effect of shading devices installed on the interior of the building, such as roller shades, curtains or venetian blinds, depends on their ability to reflect incoming solar radiation back through the window before it can be absorbed and converted to heat. Drapes may reduce annual cooling loads by 5-20% (Rudoy &amp; Duran, 1975, “Effect of Building Envelope Parameters on Annual Heating/Cooling Load”, ASHRAE Journal 7:19), and serve mainly to improve visual comfort and reduce the effect of radiant energy on building occupants near the windows. Integrated shading devices, i.e. venetian blinds placed between glass sheets in a double glazed unit or between the frames of a double window, are also in use.  
         [0007]     All shading devices interfere with one of the main purposes of windows—the provision of visual contact with the outdoors; and since their response is based on simple geometry, they are not selective in their effect. They either block out all of the incident radiation or allow it to pass through a given element of the window. The limitations of shading devices led to the development of new types of glazing materials. Modern glazing design involves the use of multiple panes of glass, with panes of differing properties combined in one window assembly. Selective transmission of light and heat may be achieved in response to changing environmental conditions. The annual energy consumption for a given enclosure may be reduced, with a concomitant improvement in illumination, by reversing the relative position of each window pane during specific periods of the year.  
         [0008]     Reversible windows for solar heating and cooling are well known in the art. For example, U.S. Pat. No. 3,925,945 discloses a glass wall assembly having a pivotally mounted frame which carries a pane of heat absorbing glass spaced from an insulating panel comprised of panes of clear glass. The heat energy absorbed by the glass may be converted into convective heat and conducted to the outside of the building during the summer months or to the interior during the winter months, after the glass wall assembly has been reversed so that the insulating panel faces the exterior side.  
         [0009]     U.S. Pat. No. 4,365,620 discloses a window which comprises a first pane that blocks infrared radiation and a second pane that transmits it and can be rotated about a horizontal axis so that the first pane faces outwardly in the summer and the second pane faces outwardly in the winter. Similarly, European Publication No. EP 922829 teaches a reversible ventilated glazing system.  
         [0010]     Although the aforementioned patents teach windows in which the orientation of the panes is reversible, the windows are nevertheless not capable of being reversed quickly and easily. They cannot be rotated on a daily basis or for a short period of time to allow for convenient and cost-effective washing of both faces of a glass window from the building interior. In order for a prior art window to be water impermeable, a sealing element such as a gasket has to be permanently affixed between the pivotally mounted frame, which carries the window, and the wall in which the frame is mounted. The sealing element therefore has to be removed, e.g. with a hand-held implement, in a time-consuming procedure. Alternatively, if the sealing element is not permanently affixed, absolute sealing is not effected due to air pockets that remain between the sealing element and the external wall. A clearance between the sealing element and the external wall, when a permanent gasket is not affixed, must be maintained to allow for the rotation of the pivotally mounted frame.  
         [0011]     U.S. Pat. No. 4,521,991 discloses a window apparatus that includes a pair of window frame assemblies which are capable of sliding and inwardly tilting relative to a jamb assembly, thereby facilitating opening and indoor cleaning. The window frames are provided with locking members to prevent tilting, and the window apparatus can withstand relatively high wind loads encountered on the upper floors of a high building due to the low stress of the locking members. Even though this window apparatus can be used for indoor window cleaning at a high level, it is not adaptable for reversing the orientation of the window panes.  
         [0012]     All the structures described above do not allow for the reversing of the relative position of each window pane during specific periods of the year in an immediate and simple manner, while maintaining the window pane assembly impervious to water and gusts of wind in either orientation.  
         [0013]     It is an object of this invention to provide a window pane assembly comprised of panes having different optical properties.  
         [0014]     It is an additional object of this invention to provide a method and apparatus for effortlessly and speedily reversing the relative position of the window panes during specific periods of the year, such that the window pane assembly is impervious to water and gusts of wind in either orientation.  
         [0015]     It is an additional object of the present invention to provide a method and apparatus for a window pane assembly that allows for indoor window washing of both sides of each pane retained in the assembly, regardless of the height above ground level.  
         [0016]     It is yet an additional object of this invention to provide a cost-effective window apparatus.  
         [0017]     Other objects and advantages of the invention will become apparent as the description proceeds.  
       SUMMARY OF THE INVENTION  
       [0018]     The present invention relates to a window apparatus comprising:  
         [0019]     i. a fixed frame having an interior surface which defines an aperture;  
         [0020]     ii. a window pane assembly comprising a frame and at least one window pane mounted in said frame, said pane having a first and a second surface, said window pane assembly being rotatably supported in said fixed frame and being rotatable with respect to said fixed frame from a first position wherein said at least one window pane is parallel to said aperture defined by said fixed frame and wherein said first surface of said at least one window pane faces the outside to a second position wherein said at least one window pane is parallel to said aperture defined by said window frame and said second surface of said at least one window pane faces the outside, said window pane assembly being further rotatable from said second to said first position; and  
         [0021]     iii. a seal assembly comprising a seal frame and at least one pliable seal carried by and exteriorly positioned with respect to said seal frame, said seal assembly being located on the inside with respect to said fixed frame and sealing said aperture from the inside, being hingedly supported in said fixed frame, and being pivotally displaceable independently of the position of said window pane assembly from a closed position in which said seal frame is parallel and adjacent to said aperture defined by said interior surface of said fixed frame to an open position in which said seal frame is spaced from and at an angle to said aperture.  
         [0022]     Preferably, a pliable seal of the seal assembly, when the frame thereof is in the closed position, is in compressed engagement with both the interior of said fixed frame and with said window pane assembly, whereby to provide a water impermeable seal.  
         [0023]     The window pane assembly may be manually rotated or remotely rotated by an actuating means.  
         [0024]     As referred to herein, the terms “outside”, “inside”, “interior” and “exterior” relate to the structure in which the window is mounted. Thus, if the window is mounted in a wall or skylight or other surface of a building, the spaces within the building constitute the inside and the space about and above the building constitute the outside.  
         [0025]     In a preferred embodiment, the window apparatus further comprises a glazing unit hingedly attached to the window pane assembly, said glazing unit being provided with at least one pane of glass parallel to, when in a closed position, and having different optical properties than the at least one pane carried by the window pane assembly, whereby said glazing unit is rotatable together with the window pane assembly, so that said glazing unit is exteriorly disposed at said first position and interiorly disposed at said second position relative to the at least one pane carried by the window pane assembly.  
         [0026]     In a winter mode, the at least one pane of glass, provided with the glazing unit, which is preferably capable of absorbing solar radiation, faces the inside. Solar radiation between 0.3-4 microns is transmitted through the at least one pane carried by the window pane assembly, which is clear and faces the outside. The at least one pane of glass provided with the glazing unit is capable of partially absorbing 30-90 percent of the energy of the incoming solar radiation, depending on local climatic conditions. The at least one pane of glass provided with the glazing unit is consequently heated and subsequently releases energy to the inside by long-wave radiation or by convective heating. At least one gap is formed between the at least one pane carried by the window pane assembly and the at least one pane of glass provided with the glazing unit, whereby heated air is able to circulate through said gap into an enclosure proximate to the window apparatus. Space heating is thereby achieved, while significantly reducing visual discomfort and damage to furnishings.  
         [0027]     In a summer mode, the window pane assembly is rotated so that the at least one pane of glass provided with the glazing unit faces the outside. Most of the short wave solar radiation between 0.3-4 microns is absorbed by the at least one pane of glass provided with the glazing unit, and is prevented from being transmitted to the inside, through the at least one pane carried by the window pane assembly, since the at least one pane of glass provided with the glazing unit is nearly opaque to a wavelength greater than 4 microns. While being heated, the energy absorbed by the at least one pane of glass provided with the glazing unit is released to the outdoors by convection or by long wave radiation. Therefore, overheating of the inside is prevented and visual comfort is improved.  
         [0028]     The present invention also relates to a method of repositioning a window pane assembly, comprising providing a window pane assembly which carries at least one window pane and which is rotatable with respect to a fixed frame; providing a mounting for a water impermeable sealing element hingedly attached to the interior of the frame; opening said mounting; applying a force to said window pane assembly to thereby displace the latter from a first position at which one side of said at least one window pane is parallel to and facing a plane formed by the exterior of the frame to a second position at which the other side of said at least one window pane is parallel to and facing a plane formed by the frame exterior, or from said second position to said first position; and closing said mounting.  
         [0029]     This method allows for the washing of windows indoors, which is particularly advantageous at the upper floors of a high building for which outdoors window washing is a costly and dangerous task.  
         [0030]     In a preferred embodiment of the invention, the method further comprises providing a glazing unit hingedly attached to the window pane assembly and which is provided with a pane of glass parallel to when in a closed position and having different optical properties than the at least one pane carried by the window pane assembly and rotating said glazing unit when in a closed position, together with the window pane assembly, from the first position to the second position, or vice versa.  
         [0031]     This method enhances winter heating and summer cooling. The glazed unit preferably faces the frame exterior during the summer months to prevent the influx of solar radiation and preferably faces the frame interior during the winter months.  
         [0032]     In one aspect, the window pane assembly is rotated by means of a microprocessor to facilitate rotation of the window pane assembly from the first position to the second position, or vice versa, in response to predetermined sensed conditions of illumination and/or temperature.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0033]     In the drawings:  
         [0034]      FIG. 1  is a perspective view of a first embodiment of the window apparatus of the invention in which a window pane assembly is in an intermediate position;  
         [0035]      FIG. 2  is a perspective view of the window apparatus of  FIG. 1  in which the window pane assembly is in a closed position;  
         [0036]      FIG. 3  is a vertical cross section of the window apparatus of  FIG. 2  taken on plane A-A;  
         [0037]      FIG. 4  is a horizontal cross section of the window apparatus of  FIG. 2  taken on plane B-B;  
         [0038]      FIG. 5  is a perspective view of a window apparatus according to a second embodiment of the invention, in which the glazing unit is shown in an open position;  
         [0039]      FIG. 6  is a perspective view of the window apparatus of  FIG. 5  in which the window pane assembly is in a closed position;  
         [0040]      FIG. 7  is a vertical cross section of the window apparatus of  FIG. 6  taken on plane C-C; and  
         [0041]      FIG. 8  is a horizontal cross section of the window apparatus of  FIG. 6  taken on D-D.  
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0042]      FIGS. 1-4  relate to one preferred embodiment of the window apparatus, generally designated by  3 . As shown in  FIG. 1 , fixed frame  7  is permanently attached to wall  5  of the structure that supports window apparatus  3 . A window pane assembly, generally designated by  9 , is rotatably displaceable about an axle (not shown) with respect to fixed frame  7 , wherein the axle is pivotally mounted in the latter. The axle may be mounted in a vertical disposition, as depicted in the drawing by the rotational direction of window pane assembly  9 , or in a horizontal disposition. As shown in  FIGS. 2 and 3 , seal assembly  15  comprising seal frame  16  and seals  23 ,  24  is pivotally attached, e.g. by means of hinges  17 , to the interior side of fixed frame  7 . When seal assembly  15  is closed, frame  16  thereof is parallel with, and pressed against, frame  10  of the window pane assembly.  
         [0043]     Fixed frame  7 , window pane assembly  9  and seal assembly  15  are rectangularly shaped. It is clear that the actual size and shape of the window apparatus are not critical, and the configuration of the present invention may be applied, mutatis mutandis, to any other size or shape. Similarly the frames shown, namely fixed frame  7 , window frame  10 , and seal assembly frame  16  or any other number of frames employed, may be fabricated from wood, aluminum, steel, plastic, or any other suitable material, alloy or mixtures thereof.  
         [0044]     For clarity, the following description relates to a window apparatus that is installed within an external wall of a building. It is understood, however, that the window apparatus of the present invention may also be advantageously adapted to a structure having any particular inclination, and therefore may also be used for a skylight.  
         [0045]     As shown in  FIG. 3 , window pane assembly  9  includes at least one window pane  8 , and preferably consists of a double-glazed unit. Each pane  8  is retained in a substantially vertical position by frame  10 . Gasket  11  provides an airtight and watertight seal.  
         [0046]     Seal assembly  15  comprises supporting frame  16  as well as seals  23  and  24  affixed to the entire periphery of frame  16 . Frame  16  is unglazed to allow for accessibility to the interior face of pane  8 . Frame  16  has an L-shaped cross section, to allow for greater structural rigidity and for the mounting thereon of the compressive seals. Seal  23  is engageable with fixed frame  7  and seal  24  is engageable with window pane assembly  9 .  
         [0047]     Seal assembly  15  is hingedly attached to fixed frame  7  by means of hinges  17 , which are located at the inside with respect to the pane assembly. The seal assembly  15  may be hinged to any of the four sides of fixed frame  7 , and may be conveniently opened and closed with a handle (not shown), or with any other opening means. When in a closed position, seal  24  is in compressed engagement with the interior side of frame  10  of the window assembly, and seal  23  is in compressed engagement with the interior side of fixed frame  7 . As shown further in  FIG. 4 , seal  23  is more outwardly positioned, that is closer to frame  16 , than seal  24 . Therefore seal  23  will prevent the passage of any water which may have collected between window pane assembly  9  and seal mounting  15 , thereby providing the window apparatus with a water impermeable seal. The water impermeability is further enhanced by water drips  25  formed within fixed frame  7 , frame  10  of the window pane assembly and sill  28 , and by drainage channel  30  formed in the bottom portion of fixed frame  7 . Drainage hole  27  drains the water that collects into drainage channel  30 , e.g. from a complementary water drip  25  formed in the underside of frame  10  (see  FIG. 3 ). Sill  28  is disposed underneath fixed frame  7 . Frames  10  and  16  are provided with brush seals  26 , which resiliently contact fixed frame  10 , to restrict the passage of air.  
         [0048]     Operationally, window pane assembly  9  may be rotated only after seal assembly  15  has been opened. After applying a force to window pane assembly  9 , which in the illustrated example is provided with two window panes, the window pane assembly is rotated. The axis about which window pane assembly  9  rotates is indicated in  FIG. 3  by  29 . The window pane assembly is continuously rotatable by 360 degrees since fixed frame  7  has a contour with no protrusions which would resist or interfere with such a rotation.  
         [0049]     In order to wash both window panes  8 , window pane assembly  9  needs to be displaced from a first position, at which one of the panes is parallel to and faces the exterior of fixed frame  7 , to a second position at which the other pane is parallel to and faces the exterior of fixed frame  7 . Similarly window pane assembly  9  at times needs to be displaced from the second position to the first position. Window pane assembly  9  is configured to come as close as possible to fixed frame  7  during rotation without contact therewith. For example, a gap of only 7 mm is needed for a 120-cm wide window pane assembly to rotate within a fixed frame having a width of 100 cm. After closing seal assembly  15 , whereby seal  23  is in compressed engagement with fixed frame  7 , seal assembly  15  may be latched shut by means of a latch (not shown) that connects frame  16  and fixed frame  7  to prevent the opening of assembly  15  due to gusts of wind. These operations allow to carry out the washing of the windows indoors, which is particularly advantageous at the upper floors of a high building for which washing windows from the outside is a costly and dangerous task.  
         [0050]     Window pane assembly  9  may be manually rotated by exerting a force on frame  10 . Window pane assembly  9  may be remotely rotated by an actuating means, such as when the window panes are massive or when strong winds are blowing. The actuating means (not shown), e.g. a motor, may communicate with the axle(s), or may be provided with any other configuration that applies a moment to window pane assembly  9 .  
         [0051]      FIGS. 5-8  relate to a second preferred embodiment of the present invention, in which window apparatus  33  is provided with glazing unit  42 . Since most of the components of window apparatus  33  are identical to those of window apparatus  3 , described hereinbefore with reference to  FIGS. 1-4 , fixed frame  37 , window pane assembly  39  and seal assembly  45  need not be described.  FIG. 5  shows glazing unit  42  in an open position, and  FIG. 6  shows glazing unit in a closed position.  
         [0052]      FIG. 7  illustrates glazing unit  42 , which is provided with pane of glass  44  having different optical properties than each pane  38  carried by window pane assembly  39 . Pane  44  may be secured, inter alia, by fixture  46  having e.g. a circular cross section and extending outward from the entire periphery of pane  44 . Fixture  46  is fabricated with two planar extensions  48 , one of which is disposed at each side of pane  44  and preferably bonded thereto at each edge thereof for support.  
         [0053]     Rotatable frame  41  of window pane assembly  39  in this embodiment is thicker than that that of frame  10  shown in  FIG. 3 , so as to allow for the placement of glazing unit  42  therein. Panes(s)  38  are laterally offset from axle(s)  43  about which window pane assembly  39  rotates. The vertical height, that is the dimension parallel to axle(s)  43 , of panes(s)  38  is greater than that of pane  44 , and consequently the height of the cavities into which panes(s)  38  and pane  44 , respectively, are insertable is also different.  
         [0054]     As shown, glazing unit  42  is hingedly attached to window pane assembly  39  by hinges  50 . Window pane assembly  39  is provided with a cavity whose periphery corresponds to the dimensions of frame  46  of glazing unit  42 , as illustrated in  FIG. 5 , so as to allow for the fixation of glazing unit  42  when closed by providing a small clearance between fixture  46  and rotatable frame  41 . A latch (not shown) is preferably provided to secure glazing unit  42  to rotatable frame  41  when the glazing unit is exteriorly positioned and exposed to a high wind load. When in a closed position, pane  44  of the glazing unit is parallel to pane(s)  38  of the window pane assembly. As a result, glazing unit  42 , when in a closed position, rotates together with window pane assembly  39 , from the first position to the second position thereof, or vice versa.  
         [0055]     Glazing unit  42  enhances winter heating and summer cooling. The glazed unit may be advantageously repositioned by rotating window pane assembly  39  to a winter mode or a summer mode. In a summer mode, glazing unit  42  is exteriorly positioned with respect to window pane assembly  39 , such that pane  44  absorbs most of the solar radiation and prevent its transmission through clear pane(s)  38  to the interior. After being heated, pane  44  dissipates the energy absorbed to the outdoors by convection and by long wave radiation. In a winter mode, the glazing unit is interiorly positioned with respect to pane(s)  38 , as shown in  FIG. 7 . After being transmitted through pane(s)  38 , solar radiation is absorbed by pane  44 . As a result pane  44  is heated, releasing the energy to the interior by long wave radiation and by convection. The provision of glazing unit  42  significantly reduces any damage to furnishings by solar radiation. In both the winter and summer modes, pane(s)  38  and pane  44  are mutually parallel.  
         [0056]     Air channel  51  is formed between pane(s)  38  and pane  44 , due to the lateral spacing between the two sets of panes. This air channel enhances air circulation around absorptive pane  44  and into the building interior. Since the height of pane  44  is less than that of pane(s)  38 , upper gap  53  and lower gap  54  are formed by the vertical spacing between rotatable frame  41  and glazing unit  42 . During the winter mode, tinted pane  44  of the glazing unit absorbs most of the solar radiation that is transmitted through clear pane(s)  38 . Pane  44  is therefore heated, following which air channel  51  is heated. The heated air then circulates through upper gap  53  and through the opening defined by the frame of the seal assembly into the enclosure. In the summer mode, pane  44  is exteriorly positioned with respect to pane(s)  38  and directs the heated air through gap  53  to the outside. It would be appreciated that even though air channel  51  and gap  53  provide a means of air circulation into the enclosure during the winter mode, the window apparatus nevertheless is airtight. Gaskets  11  which secure pane(s)  38  to the window pane assembly, brush seals  26  and seals  23 ,  24  prevent the infiltration of outside air, such as during gusts of wind or during a sandstorm, in both the summer and winter modes.  
         [0057]     Window washing can be performed as follows: According to the example of the window apparatus shown in  FIG. 7 , two panes  38   a  and  38   b  are provided in window pane assembly  39  and one glazing unit pane  44  are employed. The number of panes shown in the figures was chosen for clarity, and it is clear that any number of panes can be employed in both the window pane assembly and in the glazing unit, without any loss in efficacy or ease in repositioning. In the winter mode, in which glazing unit  42  is facing the inside, the interior face of pane  44  is washed first. Glazing unit  42 , which is hingedly attached to window pane assembly  39 , is then opened, exposing the exterior face of pane  44  and the interior face of pane  38   b  for washing. Pane  44  is then closed and secured. If the exterior face of pane  38   a  requires washing, seal assembly  45  is then opened and window pane assembly  39  is rotated 180 degrees to facilitate its washing by a person located within the enclosure. After being washed, window pane assembly  39  is rotated another 180 degrees, so that pane  38   a  is once again exteriorly positioned, and seal assembly  45  is then closed and secured to provide a weatherproof seal. In the summer mode in which tinted pane  44  is exteriorly positioned with respect to pane(s)  38 , the steps are reversed.  
         [0058]     In addition to the other methods of rotation described hereinbefore in relation to the embodiment of  FIG. 1 , window pane assembly  39  may also be automatically rotated by a microprocessor-controlled window apparatus (not shown). During those days, in which it is would be advantageous to reposition the window pane assembly at least once a day, that is to change the relative location of glazing unit  42  with respect to panes  38   a  and  38   b,  to maximize comfort and energy savings, the repositioning is controllable by means of a microprocessor-controlled window apparatus. Such an apparatus may receive input from light and heat sensors disposed at predetermined locations relative to the window pane assembly. By example, if the temperature gradient between two of these sensors is greater than a predetermined value, the seal assembly is opened, e.g. by means of a pneumatic actuator, and the window pane assembly is rotated 180 degrees, after which the seal mounting is closed.  
         [0059]     While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried into practice with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without departing from the spirit of the invention or exceeding the scope of the claims.