You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a ventilator for a glass block window and associated products. 
     2. Background Information 
     Ventilators for glass block windows are known. For example, U.S. Pat. No. 5,675,948 discloses such a ventilator in which a sash tilts away from a frame that is mounted in a glass block window. The sash, however tilts such that rain, snow and the like can be captured by the sash and directed into an opening in the ventilator. This particular ventilator also includes a screen disposed interiorly of the sash, however, that screen appears to be fixedly mounted in the frame, thus making removal thereof difficult, if not impossible. 
     What is needed is an improved ventilator for a glass block window that overcomes the shortcomings of the prior art, and particularly, the ventilator shown in U.S. Pat. No. 5,675,948. 
     SUMMARY OF THE INVENTION 
     The invention has met or exceeded the above-captioned needs as well as others. A ventilator for a glass block window is provided that includes a window frame, a window sash pivotably mounted in the window frame and a screen also pivotably mounted in the window frame. Preferably, the window sash is pivotable between a closed position and an open position such that when the window sash is in the open position, rain and snow and the like are resisted from passing through the ventilator and into the building which has the glass block window. 
     The invention also encompasses providing a ventilator as described above without the screen. Finally, a screen for a window is also provided. The screen of the invention is pivotably mounted to the window frame of the window. This screen can be used not only for the ventilator but also for other types of windows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A full understanding of the invention can be gained from the following detailed description of the invention when read in conjunction with the accompanying drawings in which: 
     FIG. 1 is an elevational view of a glass block window looking from the inside of a building in which the glass block window is installed. 
     FIG. 2 is a perspective view, partially cutaway, showing the ventilator separated from the glass block window and also showing the window sash in an open position. 
     FIG. 2A is a detailed view of one of the hinge members. 
     FIG. 2B is a cross-sectional view taken along line  2 B— 2 B of FIG.  2 A. 
     FIG. 3 is an elevational view, partially cutaway, showing the ventilator separated from the glass block window and also showing the window sash in a closed position. 
     FIG. 4 is a back perspective view, partially cutaway, showing the pivotable screen of the invention in a closed position. 
     FIG. 5 is a view similar to FIG. 4 only showing the screen pivoted to the open position. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows a glass block window  10 . The glass block window  10  consists of a plurality of square glass blocks, such as glass block  12 , arranged in a rectangular shape to form a completed glass block panel  14 . The glass blocks are joined together with a bonding type material  16  such as, for example, mortar. The ventilator  20  of the invention is mounted, preferably, in the center of the glass block window. As is known, the ventilator  20  provides a method of providing ventilation to an area enclosed by the glass block window  10 . 
     Referring now more particularly to FIGS. 2 and 3, the ventilator  20  of the invention will be discussed in more detail. The ventilator  20  includes a frame  22  that is comprised of a left jamb  24 , right jamb  26 , superior head  28  and interior sill  30 . These portions are preferably made of an extruded vinyl, although other materials, such as aluminum, can be used. The vinyl extrusions are welded together to form the frame  22 . In accordance with the invention, a sash  40  is pivotably mounted in the frame  22 . The sash  40  shown is rectangular in shape and corresponds to the dimensions of the opening in the frame  22 . The sash  40  is fixed to the superior head  28  of the frame  22  and pivots about a pivot line P—P that is generally horizontally disposed. The sash  40  includes a sash frame  42 , which includes a vertical left portion  44 , a vertical right portion  45 , a horizontal top portion  46  and a horizontal bottom portion  47 . Portions  44 - 47  are separate miter cut extruded vinyl pieces which are welded together. Mounted in the sash frame  42  is a double panel window  48 . The window  48  is mounted by any known means. It can be appreciated that the exterior pane of glass can be translucent to obscure any view into the building through the glass. The interior pane of glass can be transparent. 
     FIG. 3 also show the sash latch  50 . This is a standard pivotable latch including an extended handle portion  52  and a lower tab portion  54  that is adapted to fit into an engaging portion  56  formed in frame  22 . 
     Referring to FIGS. 2,  2 A and  2 B, the sash  40  is pivotably mounted to the frame  22  by means of a pair of hinge members  60 ,  62 . Each hinge member  60 ,  62  is similar in construction. Each hinge member includes a bar, such as bar  64  defining a lower slot  66  of hinge member  62 . A fastener attaches a first end of the bar to vertical portions of the sash frame. FIG. 2 shows one such fastener  68  which is attached to sash frame member  44 . A second fastener, such as fastener  72  of hinge member  62 , is attached to the right jamb  26 . The fastener  72  includes a head portion  73  and an underlying washer  74 . The head portion  73  and washer  74  preferably have a diameter greater than the width of the slot  66 . The second fastener  72  is disposed in the lower slot  66  (FIG.  2 A). It will also be seen that the lower slot  66  also defines a notched area  76  defined by inwardly facing notches  77  and  78 . The fastener  72  includes a bushing  79  on which the bar  64  slides against. 
     In operation, when it is desired to move the sash  40  from the closed position (FIG. 2) to the open position (FIG.  3 ), the sash  40 , if necessary, is unlocked from the frame  22  by using the sash latch  50 . The user then pushes the sash frame  42  near its bottom to cause the bottom to pivot away from the frame along the pivot line P. The pivot line P is generally horizontal in orientation and is disposed generally along the upper portion of the frame  22 , as is shown in FIG.  2 . This at first causes the bar  64  to rotate, and then to move upwardly along an angular path due to the second fastener  72 . At some point, the second fastener  72  engages the notches  77  and  78 . At that point the user applies a greater outward pressure on the sash  40  to allow the bar  64  to keep moving upward and beyond the notched area  76 . Once the second fastener  72  is past the notched area  76 , the sash  40  is in its full open position (FIG. 3) and will stay there due to the presence of the notches  77  and  78 . 
     There are several advantages to this structure and operation over the prior art. The greatest advantage is that the sash forms an awning that resists the entry of snow and rain into the opening of the ventilator. This can also include water runoff from the sides of the building in which the glass block window is mounted. This arrangement prevents moisture from lying on the interior sill  30  of the frame  22 , thus increasing the effectiveness and useful life of the ventilator. 
     In order to return the sash  40  to the closed position (FIG.  3 ), the process is reversed, with an extra inward force from the user being used to clear the second fastener  72  past the notched area  76 . The sash  40  is then pivoted back to the closed position (FIG. 2) and sash latch  50  is locked. 
     FIGS. 2 and 3 also show the large bubble type insulation bead  78  that is disposed around the edge of the sash frame  42 . This provides superior insulation properties for the ventilator to reduce heating and cooling costs. 
     Referring now to FIGS. 4 and 5, the pivotable screen  80  of the invention will be discussed. The pivotable screen  80  can be moved from a closed position (FIG. 4) to an open position (FIG.  5 ). The screen  80  includes a pair of vertically opposed frame members  82 ,  83  and a pair of horizontally opposed members  84 ,  85  which form a frame having an opening in which is disposed a standard mesh screen  88 . 
     The screen  80  is fixed in a closed position by means of a standard screen latch  90  that includes a handle portion and an extending tab portion. As is known, the tab portion  93  engages into an engaging slot formed in the jamb  24 . 
     In order to move the screen  80 , it is unlocked (if necessary) and then pivoted to the open position (FIG. 5) on pivot line P 1 . Preferably, the screen  80  is pivotably mounted in the frame  22  by means of hinge pins  95  and  96  disposed on the upper and lower left hand portions of the screen  80  which engage into complementary holes (not shown) in the frame  32  (FIG.  4 ). When it is desired to move the screen  80  to the closed position (FIG. 4) the process is merely reversed, and the screen latch  90  is locked. 
     It will be appreciated that the pivotable screen is not limited to application for glass block window ventilators, but can be used in association with any type of window whether double hung, casement or awning type windows. The advantages of the pivotable screen are numerous. In the case of a ventilator for a glass block window, the pivotable screen allows for easy access of entry for certain household items, such as garden hoses and electrical cords. With the prior art ventilators, this was not possible, as the screen was fixed in the frame. Furthermore, the pivotable screen allows for easier access to clean the interior of the sash and the interior portion of the window. If the screens are used on double hung windows and thus disposed exteriorly of the window surface, the screen can be merely pivoted out of the way instead of being totally removed, thus making cleaning of the exterior surface of that double hung window much easier. 
     It will be appreciated that a ventilator for a glass block window is provided that has numerous improvements over the prior art. A pivotable screen, which can be used not only for the ventilator but also for other types of windows, is also provided. 
     While specific embodiments of the invention have been disclosed, it will be appreciated by those skilled in the art that various modifications and alterations to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breath of the appended claims and any all equivalents thereof.

Summary:
The invention comprises a ventilator for a glass block window that includes a window frame, a window sash pivotably mounted in the window frame and a screen also pivotably mounted in the window frame. The window sash is pivotable between a closed position and an open position such that when the window sash is in the open position, rain and snow and the like are resisted from passing through the ventilator and into the building which has the glass block window. The invention also encompasses providing a ventilator as described above without the screen. Finally, a screen for a window is also provided. The screen is pivotably mounted to the window frame of the window. This screen can be used not only for the ventilator but also for other types of windows.