Patent Abstract:
A window frame provided with a tapered sub-sill that is mounted on the wall and via a plurality of spaced spacers tapered in the opposite direction to support the main frame sill element in its substantially horizontal position. The use of the tapered sub-sill and tapered spacers permit the sealing membrane positioned between the wall structure and the wall facing to pass therebetween and provide a good seal and provide a solid base for the main sill. In the preferred arrangement, a snap in seal is connected to the outside bottom edge of the sill and forms a seal between the facing layer and the sill and provides a projecting flashing to redirect rain.

Full Description:
FIELD OF INVENTION 
     The present invention relates to window frame structure, more particularly, the present invention relates to a sill structure facilitating draining and particularly adapted for use with walls with internal wall cavities. 
     BACKGROUND OF THE INVENTION 
     There are many, many different forms and shapes of window frame members generally made by extrusion aluminum or polyvinylchloride (PVC) that are connected together to form the window frame for mounting windows in position in the window opening. 
     U.S. Pat. No. 5,666,773 issued Sep. 3, 1997 to Librande et al. shows a number of different arrangements of extruded materials and their fabrication to form window frames. This patent discloses a tapered spacer element to mount a frame element on a sloping sill and uses extruded trim members to connect to the frame to trim the window frame to the surrounding wall structure. 
     BRIEF DESCRIPTION OF THE PRESENT INVENTION 
     It is an object of the present invention to provide an improved window frame structure particularly an improved sill structure. 
     It is a further object of the present invention to provide a snap-in seal that may be used particularly with cavity wall to seal the window frame to the wall facing around the periphery of the window. 
     Broadly, the present invention relates to a window frame comprising a sub-sill having a mounting surface for positioning in a window opening and a sloping surface extending in an acute angle from the side of the sub-sill that faces outward relative to the window opening when the sub-sill is mounted in the window opening. A plurality of discreet spacer elements overlie the sub-sill and are positioned in axially spaced relationship relative to the longitudinal axis of the sub-sill. A main sill has a main mounting surface, cooperating fastening elements on the main surface and is connected to the spacers by a snap type connection. The spacer position the main sill substantially parallel to said mounting surface and the main sill is connected to the sub-sill. 
     Preferably, said cooperating fastening elements providing the connection between said spacers and said main sill comprise a snap fits between an arm at one end of each of said spacers and a tongue and groove connection between said main sill and a second arm on each of said spacer adjacent an opposite end of said spacer to said one end. 
     Preferably, said main sill has a axially extending nailing strip projecting downwardly from said main sill and said snap fit between said one arm and said main sill employs an undercut on said nailing strip. 
     Preferably, said window frame further comprises a compression gasket, said compression gasket in place, said compression gasket having a rib at one end and a deflectable element at its opposite end, a groove in said main seal in which said rib is received when said gasket is mounted on said main sill and an undercut on said main seal into which said deflectable element is snaped over when said gasket is mounted on said main sill. 
     Preferably, said gasket includes plurality of deformable strips interconnected with said gasket and adapted to contact the facing portion of a wall. 
     Preferably, the compression gasket includes a flashing member projecting forward therefrom. 
     The present invention also relates to a wall structure having an air space positioned between a structural wall portion and a facing wall portion, a window opening through the wall. A window frame including a sub-sill having a mounting surface and a sloping support surface extending at an acute angle from said mounting surface is -sill mounted in the window opening and on the main supporting wall with said support surface sloping upward and inward relative to said window opening. A sealing membrane extends in said air space and is positioned against said structural wall portion and passes into the window opening over the sloping face of the sub-sill to provide a seal for said structural wall portion. A plurality of spaced tapered spacer elements are positioned in overlying relationship to the sloped wall and overlying membrane that extends up the sloped wall. Cooperating fastener elements releasable connect each of the spacer members to a main sill member and a connector connects said main sill member to said sub-sill member. 
     Preferably said main sill member has an axially and downwardly extending nailing flange that passes into said air space and is positioned against said membrane immediately adjacent to said window opening in said air space. 
     Preferably, said structure further includes a compressible gasket and a releasable connection connecting said compressible seal to said main seal. 
     Preferably, said compressible gasket includes a flashing projecting outwardly of said wall. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further features, objects and advantages will be evident from the following detailed description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings in which; 
     FIG. 1 is a side elevation of the sill structure of the present invention. 
     FIG. 2 is an enlarged cross-section showing a portion of the main frame member and how it cooperates with the sub-sill and spacers of the present invention. 
     FIG. 3 is a section in plan showing the side jam construction particularly suited for use in combination with the sill of FIG.  1 . 
     FIG. 4 is a vertical section through the window frame illustrating a head construction particularly suited for use with the present invention on cavity walls. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The window frame  10  of the present invention is composed of a main element  12  which forms the main sill element  12  in the sill structure shown in FIGS. 1 and 2, the main jam member in the jam structure shown in FIG.  3  and the main head member  12  in the head structure shown in FIG.  4 . This main element  12  in the illustrated arrangement is a hollow body having an inner flange  14  and an outer flange  16 , the inner flange  14  is positioned at the innermost side of the structure and projects upward relative to the window frame and the outer flange  16  is at the outermost side of the member  12  and projects downward relative to the window frame. The main mounting surface  18  of the member  12  is provided with a formed cavity  20  with a tongue  22  projecting into the cavity  20  toward the outmost side of the member  12  and extending substantially parallel to the surface  18  from an inner wall  24  of the cavity  20  that is closest to the flange inside  14 . 
     About mid-width of the member  12  is a mounting flange  26  which extends substantially the full length of the member  12  and is substantially perpendicular to the surface  18 . The mounting or nailing flange  26  is formed with ramps  28  and  30  one on each side of the flange  26 . These ramps each form one side of an undercut groove  32  and  34  respectively positioned between its ramp and the surface  18 . These grooves  32  and  34  functions to cooperated with elements on additional parts of the structure to provide snap connections as will be described hereinbelow. 
     In the sill structure illustrated in FIG. 1, the main element  12 , which in this case is the main sill element  12  is shown mounted (via the sub-sill  50  and spacers  70  as will be described below) in the window opening  36  of the wall structure  38  formed with an air space  40  along the outside face of the support wall structure  42  and the inside of a facing structure  44 . The facing wall structure  44  forms the decorative and/or exposed face of the wall protecting the structural wall portion from the elements. 
     To mount the sill  12  in position, a tapered sub-sill  50  which provides important portion of the present invention is first mounted in the opening  36  with a support surface  52  resting on the bottom of the opening  36  and having its outer end  54  adjacent to the outside surface of the structural portion  42  i.e. at the air space  40 . The upper surface  56  of the sub-sill  50  slopes at an acute angle to the support surface  52  so that in mounted position in the opening  36  the surface  56  slopes upwardly and inwardly into the opening  36  i.e. in toward the inside of the wall  38 . 
     The sub-sill  50  is provided with an inner mounting flange  58  through which a connector  60  connects the sub-sill to the main sill  12 . In the illustrated arrangement, the connector  60  is a screw (a plurality of screws) interconnecting the sub-sill  50  and main sill  12 . The sub-sill is anchored to the main or support wall  42  by any suitable means in the illustrated arrangement, a screw  62  (plurality of screws  62 ) has been shown for making this connection. 
     In the wall structure, a sealing membrane  64  is positioned in the air space  40  and extends over substantially the full outer surface of the support wall  42 . The membrane extends into the opening  36  over and overlies the sub-sill  50  to provide a seal for the sub-sill  50  and preferably extends right up to the top of the inner flange  58 . 
     The plurality of spacers  70 ( generally less than 2 inches (50 cm) in length (measured parallel to the longitudinal axis of the sill  12  and/or sub-sill  50 ) are positioned in axially spaced relationship (relative to the sill  12  and/or sub-sill  50 ) in overlying relationship relative to the sloping surface  56  of the sub-sill  50 . Each spacer  70  is formed with a supporting surface  72  which is in facing relationship to the surface  56  and sandwiches the membrane  64  between it and the surface  56  to clamp the membrane firmly in position. 
     Each spacer  70  is provided with a plurality of supporting ribs, a center rib  74  which rests against the surface  18  of the member  12 , a outer rib  76 , the upper end of which also rests against the surface  18  but which also is provided with a rib  78  that is received within the cavity  32  on the flange  26 . The inner end of each spacer  70  is provided with a gripping flange or rib  80  that is provided with a slot  82  adapted to receive a tongue  22  falls in the cavity  20  and is provided with a tab  84  that is received in the cavity  20  and bears against the surface  20 A of the cavity  20  and forms the upper wall of the slot  80 . 
     Before the member  12  is mounted on the sub-sill  50 , plurality of spacers  70  are snapped into position by positioning the groove  82  onto the rib  22  and then forcing the spacers  70  so that the flange or rib  76  at its free end engages the ramp  28  on the flange  26  of the main sill  12  is deflected so the projection  78  snaps into the undercut  32  to lock the spacer  70  into position. 
     A compressible seal or gasket  90  is preferably mounted on the main element  12  (i.e. for the sill and the jam) by a snap fit (see FIGS. 1,  2  and particularly FIG. 3) via a flange  92  that is received within an axially extending groove  94  in the member  12  positioned adjacent to junction between the surface  18  and the projecting flange or outside flange  16  and a deflectable rib or flange  96  at its inner side. This flange or rib  96  is deflected by the ramp  30  cooperating with the surface  98  of the undercut portion  100  to deflect the flange  96  and position the undercut portion  100  within the groove  34  and form a snap fit between the seal element  90  and the main element  12 . 
     The seal element or gasket element  90  is formed with a plurality of flexible sealing ribs or the like  102  that extend therefrom and are positioned to contact the adjacent surface  104  or the facing portion  44  of the wall  38 . 
     This type of seal member  90  is used along three sides of the window, i.e. the two jam portions and the sill to provide a seal on these three sides of the window between the frame member  12  and the facing wall portion  44 . 
     With respect to sealing of the sill, sealing member  90  is replaced by a sealing member  90 A substantially the same as member  90  but having a flashing member  106  that projects downwardly from sealing member  90 A and outward relative to the wall  38 . The flashing member  106  directs water away from the wall  38 . 
     In the FIGS. 3 and 4 embodiments, the ribs or the like  102  all extend from the main portion of the snap-in seal  90 , however, in the FIG. 1 embodiment where the snap-in seal  90 A also functions as flashing one of the flexible sealing members have been shown as being connected to the extension of the seal forming the flashing  106 . 
     Referring to FIG. 4 where the member  12  is used as a head, it is used in combination with an upper head flashing element  200  which is formed by a continuous extrusion having an outer flange  202  which rests in face to face relationship with the flange  16  of the member  12  and with a mounting flange  204  extending substantially parallel thereto at the opposite side of the element  200 . The flange  204  is adapted to extend up the wall face  66  and is connected thereto by suitable screws  206 . The mounting flange has an indented surface portion  204 A that extends over and is adapted to receive the mounting element  26  of the member  12 . The flange  204  also has a projecting element  208  over the water sealing membrane  64  passes to cover the connecting screws or connectors  206  and thus seal the system. 
     The flashing  200  is formed with a top member having a downward and outwardly sloping surface  210  to direct any moisture out from within the cavity  40 . 
     In the illustrated arrangement, suitable support members and the like as indicated for example at  212 , form part of the member  200  to provide the required strength characteristics and the member  200 . 
     At the inner ends of the head and jams, a suitable rod  220  and cocking  222  is used to provide a seal and the membrane  64  or a portion of the membrane  64  is extended as indicated at  64 A for the head in FIG.  4  and is seal to the inner vapor barrier  230  as schematically illustrated at  232 . 
     Referring back to FIGS. 1 and 2 (the sill assembly), in this arrangement, the vapor barrier  230  is sealed directly to the rearwardly projecting flange  240  of the sub-sill  50  as indicated by the seal  242  so that the membrane  64  is sealed to the flange  78  and the vapor barrier  230  is sealed to the flange  240  of the sub-sill  50  and thereby provide a substantially complete seal around the structural wall  42  at the window opening. 
     It will be apparent that suitable drain holes will be provided in the main member  12  as required depending on the application. 
     Having described the invention, modifications will be evident to those skilled in the art without departing from the scope of the invention as defined in the appended claims.

Technology Classification (CPC): 4