Patent Publication Number: US-6340202-B1

Title: Window structure for mass transit vehicle

Description:
This application is related to a series of four further applications all filed simultaneously with this application and assigned to the same assignee as follows: 
     Application Ser. No. 09/496,686 filed Feb. 3, 2000 and entitled Interior Structure of a Mass Transit Vehicle. 
     Application Ser. No. 09/497,634 filed Feb. 3, 2000 and entitled Passenger Lighting System for Mass Transit Vehicle. 
     Application Ser. No. 09/497,633 filed Feb. 3, 2000 and entitled Side Impact Structure of Mass Transit Vehicle. 
     Application Ser. No. 09/496,684 filed Feb. 3, 2000 and entitled Body Structure for Mass Transit Vehicle. 
     The disclosures of the above applications are incorporated herein by reference. 
    
    
     This invention relates to window structure for a mass transit vehicle. 
     This application is related to a series of four further applications all filed simultaneously with this application and assigned to the same assignee as follows: 
     Application Ser. No. 09/496,686 filed Feb. 3, 2000 and entitled Interior Structure of a Mass Transit Vehicle. 
     Application Ser. No. 09/497,634 filed Feb. 3, 2000 and entitled Passenger Lighting System for Mass Transit Vehicle. 
     Application Ser. No. 09/497,633 filed Feb. 3, 2000 and entitled Side Impact Structure of Mass Transit Vehicle. 
     Application Ser. No. 09/496,684 filed Feb. 3, 2000 and entitled Body Structure for Mass Transit Vehicle. 
     The disclosures of the above applications are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     In public transport vehicles particularly buses but also including rail cars, it is conventional to provide a structure having a side wall frame which is cladded on its inside and outside surfaces to form a side wall structure. Where windows are required, the frame defines a window opening with the cladding coming up to the edge of the window opening and leaving the window opening open for the insertion of a separate window frame structure which attaches to the frame of the side wall over the cladding and holds the window in place. 
     In most windows for such public transit vehicles, it is necessary to provide a window pane structure which pivots relative to the frame to allow an opening action for emergency escape. 
     There has been up till now a significant problem of moisture leakage in window structures of this type in that the moisture enters between a multi part window frame structure and the cladding, penetrating either the interior of the vehicle, or often more dangerously, into the wall structure of the vehicle causing hidden corrosion. 
     Some examples of window frame structures of this general type are shown in U.S. Pat. No. 5,544,457 (Labrecque) assigned to Prevost and U.S. Pat. Nos. 5,787,643 and 5,941,022 (Schmuck) assigned to Excel Industries. 
     SUMMARY OF THE INVENTION 
     It is one object of the present invention, therefore, to provide an improved window assembly for mounting in the window opening of a public transit vehicle. 
     According to a first aspect of the invention there is provided a public transit vehicle comprising: 
     a vehicle body having: 
     a roof, 
     two side walls each extending longitudinally of the vehicle, 
     a vehicle floor connected to the side walls and spanning therebetween; 
     each side wall including a plurality of window openings at spaced positions longitudinally of the side wall each for receiving a respective window; 
     each window including a rectangular window frame fastened to the side wall and carried thereby so surround the window opening defining a window plane parallel to the side wall; 
     the window frame comprising a pan defined by four side pan members each along a respective side of the central window opening, each pan member being shaped in cross section to define a web portion generally at right angles to the window plane, an exterior flange portion connected to the web portion at an exterior edge thereof and extending generally at right angles to the web portion outwardly from the window opening and an interior flange portion connected to the web portion at an interior edge thereof and extending generally at right angles to the web portion inwardly into the window opening; 
     each window including a rectangular window pane structure having a window pane in the window plane and a surrounding frame member attached to the pane; 
     the window pane structure being mounted in the window frame and including sealing elements butting against the window frame; 
     the web portion, exterior flange portion and interior flange portion being formed as an integral structure so as to prevent the penetration of exterior moisture therethrough to the interior. 
     Preferably the pan is attached to the side wall by a structural interconnection which is formed substantially wholly by an adhesive connection between the exterior flange and an adjacent surface of the side wall and an adhesive connection between the web portion and an adjacent surface of the side wall. 
     Preferably the side wall includes a side wall frame having four frame members each on a respective one of two sides, top and bottom respectively of the window opening, each frame member defining an exterior wall and a web wall and wherein the exterior flange is attached by adhesive to the exterior wall and the web portion is attached by adhesive to the web wall. 
     Preferably the pan is molded as an integral structure. 
     Preferably a bottom one of the pan members includes a further web portion attached to an outermost edge of the exterior flange and extending therefrom away from the window plane and a further flange portion attached to an outer edge of the further web portion and extending therefrom away from the window opening, wherein the side wall includes a cladding member carried thereby underneath the windows and wherein the further flange portion overlaps a top edge of the cladding member and is attached thereto by adhesive. 
     Preferably there is provided a support member for the pane structure along a top one of the pan members, the support member defining a hinge allowing pivotal movement of the pane structure about a horizontal axis from a closed position to an open position, the hinge being arranged above the web portion of the top pan member such that the frame members are inserted into the pan in the closed position and pivot out of the pan in the open position. 
     Preferably the frame members in the closed position abut the pan members so that the pan members and the frame members co-operate in providing structural strength for the window. 
     Preferably the hinge allows removal of the pane structure from the frame structure as an integral unit. 
     Preferably the hinge comprises a part cylindrical receptacle within which is received a part cylindrical insert of the pane structure allowing pivotal movement of the pane structure about a horizontal axis defined by the receptacle and wherein the part cylindrical receptacle and the part cylindrical insert are arranged such that the insert can be removed out of the receptacle in a transverse direction relative thereto after pivotal movement of the pane structure beyond a predetermined position thereof. 
     Preferably the insert includes end insert members therein extending axially beyond respective ends thereof and wherein the support member includes end mounting blocks thereon to prevent removal of the insert unless the mounting blocks are removed. 
     Preferably the support member forms part of a drip rail member attached to the side wall above the top pan member and defining a generally horizontal drip channel extending along the side wall. 
     Preferably the top pan member includes a flange portion extending upwardly therefrom and overlapped by the drip rail member. 
     Preferably the side wall includes a side wall cladding member mounted on the side wall above the window and wherein the cladding member has a bottom edge flange overlapping a top edge flange of the drip rail member. 
     Preferably the frame member of the pane structure includes a first portion adjacent the exterior flange portion and a second portion projecting across the web portion to a position adjacent the interior flange portion, and wherein the window pane is mounted on an exterior surface of the frame member and extends to a position on the frame member at the first portion so as to overlie at least a part of the exterior flange portion. 
     Preferably there is provided a resilient sealing member attached to the frame member and having a first lip overlying an edge of the window pane and a second lip bridging a space between the first portion of the frame member and the exterior flange portion. 
     Preferably there is provided a resilient seal between an interior surface of the first portion and an exterior surface of the exterior flange portion. 
     Preferably at least one of the frame members of the pane structure includes a latch lever pivotally mounted inside a hollow interior thereof, the latch lever being engageable with a pin member carried on the frame and projecting through the web of the pan at a position adjacent the latch lever for projecting into the hollow interior of said one of the frame members, the latch lever including a positive locking cam action on the pin. 
     According to a second aspect of the invention there is provided a public transit vehicle comprising: 
     a vehicle body having: 
     a roof, 
     two side walls each extending longitudinally of the vehicle, 
     a vehicle floor connected to the side walls and spanning therebetween; 
     each side wall including a plurality of window openings at spaced positions longitudinally of the side wall each containing a respective window; 
     each window including a rectangular window frame fastened to the side wall and carried thereby so surround the window opening defining a window plane parallel to the side wall; 
     the window frame comprising a pan defined by four side pan members each along a respective side of the central window opening, each pan member being shaped in cross section to define a web portion generally at right angles to the window plane, an exterior flange portion connected to the web portion at an exterior edge thereof and extending generally at right angles to the web portion outwardly from the window opening and an interior flange portion connected to the web portion at an interior edge thereof and extending generally at right angles to the web portion inwardly into the window opening; 
     each window including a rectangular window pane structure having a window pane in the window plane and a surrounding frame member attached to the pane; 
     the window pane structure being mounted in the window frame and including sealing elements butting against the window frame; 
     wherein there is provided a support member for the pane structure along a top one of the pan members, the support member defining a hinge allowing pivotal movement of the pane structure about a horizontal axis from a closed position to an open position, the hinge being arranged above the web portion of the top pan member such that the frame members are inserted into the pan in the closed position and pivot out of the pan in the open position. 
     According to a third aspect of the invention there is provided a public transit vehicle comprising: 
     a vehicle body having: 
     a roof, 
     two side walls each extending longitudinally of the vehicle, 
     a vehicle floor connected to the side walls and spanning therebetween; 
     each side wall including a plurality of window openings at spaced positions longitudinally of the side wall; 
     each window including a rectangular window frame fastened to the side wall and carried thereby so surround the window opening defining a window plane parallel to the side wall; 
     the window frame comprising a pan defined by four side pan members connected at corners of the pan, each pan member being shaped in cross-section to define a web portion generally at right angles to the window plane, an exterior flange portion connected to the web portion at an exterior edge thereof and extending generally at right angles to the web portion outwardly from the window opening and an interior flange portion connected to the web portion at an interior edge thereof and extending generally at right angles to the web portion inwardly into the window opening; 
     each window including a rectangular window pane structure having a window pane in the window plane and a surrounding frame member attached to the pane; 
     the window pane structure being mounted in the window frame and including sealing elements butting against the window frame; 
     wherein at least one of the frame members of the pane structure includes a latch lever pivotally mounted inside a hollow interior thereof, the latch lever being engageable with a pin member carried on the frame and projecting through the web of the pan at a position adjacent the latch lever for projecting into the hollow interior of said one of the frame members, the latch lever including a jaw for receiving and engaging the pin, the jaw being arranged to provide a positive locking cam action on the pin. 
     Preferably the latch lever is provided in the bottom frame member. 
     Preferably the latch lever is operated by an actuating rod extending along the frame member and wherein there is provided an actuating handle mounted on the vehicle and pivotal relative thereto for driving movement of the actuating rod. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     One embodiment of the invention will now be described in conjunction with the accompanying drawings in which: 
     FIG. 1 is a vertical cross-sectional view through a public transit vehicle according to the present invention. 
     FIG. 2 is a side elevational view of one part of the vehicle of FIG.  1 . 
     FIG. 3 is a similar vertical cross-sectional view to that of FIG. 1 on an enlarged scale and showing the window assembly only at a top of the window assembly including the pane structure, the frame and the mounting for the frame. 
     FIG. 4 is a similar cross section to that of FIG. 3 showing the window pane structure in the opened position. 
     FIG. 5 is a front elevational view of one corner of the window in the position of FIG.  3 . 
     FIG. 6 is a similar cross-section to that of FIG. 3 showing the bottom of the window assembly. 
     FIG. 7 is a horizontal cross section through two adjacent window frames at the post between the window openings. 
     FIG. 8 is a similar cross section to that of FIG. 6 on an enlarged scale and taken through a window latch in the bottom frame of the window pane structure. 
     FIG. 9 is an isometric view partly broken away to show the latch of FIG. 8 including a central operating lever for actuating two latching arrangements and showing the latch lever in a closed latched position. 
     FIG. 10 is an isometric view similar to that of FIG. 9 showing the latch lever in an open unlatched position. 
    
    
     DETAILED DESCRIPTION 
     The vehicle  10  comprises a floor  11 , side walls  12  and  13  and a roof structure  14 . The vehicle includes a central aisle  15  between two rows  16  and  17  of passenger seats. Each side wall includes a row of windows  18  commencing at a top rail  19  and extending downwardly to an intermediate rail  20 . Beneath the windows the side wall is closed to define a closed cladded section  21 . 
     The side wall structure further includes a plurality of vertical posts  22  at positions longitudinally of the side wall and extending from the floor structure  11  to the rail structure  19 . The window openings are thus defined between the rail structure  19  and the rail  20  and in between the posts  22  and window frame assembly  23  is inserted into the window opening so defined. 
     The side wall is clad on its exterior surface by a coping cladding panel  24  extending between the roof structure and the top rail  19  and by a side wall cladding panel  25  which extends along the sidewall underneath the window openings together with a plurality of impact panels  26  arranged edge to edge along the side wall underneath the sidewall panel  25 . 
     The details of the cladding panels and the structure of the side wall form the subject matter of separate ones of the above identified co-pending applications, the subject matter which is incorporated herein by reference. 
     Turning now to FIGS. 3,  6  and  7 , the window assembly  23  is shown in cross section. The window assembly  23  comprises an external window frame or pan  30  formed by four side frame members connected together at right angle corners so as to form a complete surrounding frame structure which can be inserted into the window opening in the side wall. The side frame members are preferably integrally molded so that the corners are integral but can also be formed from individual elements welded or otherwise mechanically connected at the corners. The side frame members are thus preferably integrally molded using either sheet molding compound, a material well known to one skilled in the art, or other material which forms an integral structure with suitable finished surfaces and suitable strength. This molding avoids any connections which could leak but other connection techniques can be used which allows individual elements to be connected together at the corners in a manner which forms ineffectively integral frame or pan structure resistant to leaks between the members at the corners. 
     The top frame member  31  is shown in FIG.  3 . Two of the side frame members  33  of adjacent window openings are shown in FIG.  7  and the bottom frame member  32  is shown in FIG.  6 . 
     Each frame member  31 ,  32 ,  33  includes a web portion  35  which extends generally at right angles to the plane  36  of the window opening. At the exterior edge of the web portion  35  is attached an exterior flange  37  lying generally parallel to the plane  36 . At the interior edge  38  of the web portion is provided an interior flange  39  which extends from the web portion generally parallel to the plane  36 . The exterior flange  37  extends outwardly of the web portion, that is outwardly of the window opening onto the exterior surface of the side wall structure. The interior flange  39  extends from the edge  38  of the web portion inwardly of the window opening so as to form a lip covering an external surface  12 A around the window opening. The web portion, the exterior flange and the interior flange are formed integrally as explained previously and each is substantially imperforate so that there is little or no possibility for the penetration of moisture through the frame structure. 
     At the outermost edge of the exterior flange  37  there is provided a projection portion  40  which turns inwardly toward the exterior surface  12 A of the side wall structure followed by a second web portion  41  which projects generally at right angles to the plane  36  that is in the exterior direction away from the surface  12 A. At the end of the second web portion  41  furthest spaced from the surface  12 A is provided a further flange portion defining a lip  42 . This extends parallel to the plane  36  and thus parallel to the surface  12 A but is spaced from the surface  12 A as an overhanging lip portion extending to a lip edge  43 . 
     The structure defined by the web portions and flanges is integral with the previously described portions of the pan. The cross section of all four of the frame sides is identical to the above described elements. The closed pan is attached to the window opening as defined by the top rail  19 , the bottom rail  20  and the two vertical posts  22  by a first portion  45  of adhesive inserted between the inside surface of the exterior flange  37  and the outside surface of the respective frame member  19 ,  20 ,  22 . A second portion  46  of adhesive is inserted between the web  35  and the inwardly facing surface  47  of the web portion  48  of the respective frame member  19 ,  20 ,  22 . It will be noted that the first portion  45  is received between the projection  40  and the corner of the frame member. The portion  46  is received between the corner  48  of the frame member and the edge  35 A of the web  35 . The web  35  is arranged at a slight angle to the surface  47  so that the portion  46  of adhesive is generally triangular and increases in thickness. It will be noted that the edge  35 A is spaced inwardly from the corner  48  at the interior of the frame member. Thus the pan does not project into the interior but is either located at the corner, as shown in FIG. 6, or is spaced from the corner  48  to the exterior of that corner that is towards the exterior of the side wall, as shown in FIG.  7 . 
     The pan is thus formed in a single piece and is fastened at the exterior surface of the frame member of the sidewall and is supported within the frame members wholly by the adhesive attachment provided by the adhesive portions  45  and  46 . There is no necessity for any couplings which clamp the pan to the interior surface of the frame member. The adhesive attachment is sufficient to provide the structural requirement for holding the pan in place within the window opening and providing the necessary seals. 
     In an alternative arrangement (not shown), the interior flange  38  may be stiffened by a member which is attached on its interior surface and which spans from that interior surface to the interior surface of the frame member. Such a stiffening member does not significantly act to provide structural strength holding the window pan in place but simply provides a stiffening of the flange to prevent its cracking or breakage should the window pane structure be slammed into the closed position abutting the pan. 
     As shown in FIG. 6, the lip portion overlaps a top edge  25 A of the panel  25 . Further detail concerning construction of this panel is shown and described in one of the above co-pending applications, the disclosure which is incorporated herein by reference. 
     As shown in FIG. 7, the lip portion  42  of the side frame member of the pan approaches but is spaced from the lip portion  42 A of the side portion of the pan of the next adjacent window frame construction leaving a space  42 B therebetween for expansion and tolerances. A facing band or strip  42 C is applied over recessed sections  42 E of the adjacent portions  42  and  42 A. The recessed sections overlie a strip of insulation material  42 F on the exterior of the post  22 . The strip  42 C is attached to the recessed sections by adhesive material  42 D thus providing an attractive strip vertically between the two window frames and allowing for thermal expansion and contraction. 
     As shown in FIG. 3, the profile of the top pan member is yet further supplemented by an inturned web portion  50  generally parallel to and spaced outwardly from the lip portion  41  and connected to the outermost edge of the lip portion  42 . Further at the edge of the web portion  50  adjacent the outside surface  12 A is provided a yet further flange  51  which extends outwardly from the pan structure that is upwardly of the outside surface  12 A away from the window opening to a projection  52  turned into contact with the surface  12 A. This defines an area for receiving a further portion of adhesive  53  thus attaching the flange  51  to the surface  12 A. The flanges  51  and  37  and the corresponding adhesive portions  53  and  45  thus provide a double seal arrangement effectively preventing the penetration of moisture inside the pan into the interior. Yet further the flange  51  is covered by a mounting assembly  55  for a window pane structure  56  carried in the window pan. 
     The window pane structure as best shown in the cross section of FIG. 6 comprises an external laminated or tempered glass pane  57  which is attached to and supported by a rectangular surrounding frame  58  defined by four frame members  59 , formed for example of aluminum, which are connected at mitre joints at four corners. One of the frame members is shown in FIG. 6 in cross section and it will be appreciated that each of the other frame members is substantially identical so that the frame members can be connected together by mitre joint at the corners but the top frame member shown in FIG. 3 includes additional elements for attachment to the mounting  55  as described in more detail hereinafter. 
     The frame member  59  comprises generally a hollow rectangular section  60  having an inner wall  61 , an outer wall  62 , an interior wall  63  at right angles to the walls  61  and  62  and an exterior wall  64  parallel to the wall  63 . The wall  64  includes an extension portion  65  extending beyond the wall  62  in a direction outwardly of the window opening to a flange  66  at right angles to the wall  64  and extending toward the exterior just beyond an edge  57 A of the glass pane. 
     Attached to the extension portion  65  and extending parallel to the wall  64  is provided a projecting portion  68  which lies parallel to and spaced from the interior surface of the glass pane to locate the frame member relative to the glass pane. This leaves between the exterior surface of the projecting portion  68  an area for receiving an adhesive  69  which fills the area adjacent the surface  64  and adhesively bonds the frame member to the interior surface of the glass pane. 
     The frame member at the bottom and sides carries two separate seal members for effecting a seal between the frame member and the pan. The first seal is indicated at  70  and is mounted on the exterior of the glass pane. A second bulb seal  71  is mounted by adhesive on the flange  37  and is compressed, in the closed position of the pane structure, by a portion of the interior surface of the extension portion  65  which is parallel to the flange  37 . 
     The seal  70  comprises a mounting leg  74  projecting into a slot  73  in the flange  66 , the slot  73  facing in the exterior direction so as to define an open mouth at the exterior surface of the flange  66 . The leg is held in place by transverse fins abutting the sides of the slot. The leg  74  carries two lips  72 A and  72 B which extend generally at right angles to the leg. The lip  72  bridges the space between the flange  66  and the edge  57 A of the glass pane. The lip  72 A bridges the space between the flange  66  and the lip portion  42  of the pan. The lips  72 A and  72 B form a common curved shape so as to provide an attractive appearance along the edge of the glass pane. The lip  72 A thus forms a first seal against the lip portion  42  to prevent the penetration of moisture and/or air into the area between the frame member and the pan. 
     The same sealing arrangements can be seen in FIG. 3 for cooperation with the top frame member and in FIG. 7 with the side pan member. At the top only, a third bulb seal  72 , for extra sealing effect where there is most likelihood of water penetration, is located at the interior flange  39  and abuts against the wall  63  in a third sealing action. The third seal is similar to the second seal and is adhesively attached to the interior flange  39  and projects therefrom toward the wall  63  against which it is compressed in the closed position of the window frame. 
     A resilient mounting profile  75  is provided between the frame member and the pane and includes a leg  76  projecting into the space between the flange  68  and the wall  64  and a body extending from the leg to the interior surface of the pane thus closing off the area containing the adhesive  69 . The body defines a slot  75 A for supporting a pane  75 B of polycarbonate to provide a double glazing arrangement which protects the inside surface of the main pane. The profile  75  can be pealed back to allow the release and replacement of the pane  75 B which flexes out of its position. 
     The interior cladding  175  includes a panel  176  which covers the inside surface of the frame and then curves inwardly and toward the exterior at a curved portion  177  to an edge  178  terminating closely adjacent but spaced from the pane  75 B. At the bottom only, a perforated grille  179  is attached at the edge  178  and closes the gap with a lip  180  in engagement with the pane. The grille  179  allows heated air  182  to escape from the area  181  behind the panel  176  over the interior flange of the pan, around the bottom frame member onto the window for de-fogging. The profile  75  includes a lip seal  75 C which projects from the body toward the portion  177 . At the top and sides, the lip seal  75 C butts the portion  177  and provides a seal. At the bottom, the lip seal butts a portion of the grill  179  but allows the flow of air. The construction of the air supply forms the subject of one of the above applications and can be consulted for further details. 
     In an alternative arrangement (not shown) the protector pane  75 B is omitted and the profile  75  is shaped without the slot  75 A. 
     Turning now to FIGS. 3,  4  and  5 , the mounting assembly  55  by which the pane structure  56  is mounted in the pan is shown in detail. Thus the mounting assembly  55  comprises a connector  80  attached to and carried by the exterior edge of the flange  66 . The connector  80  comprises a wall extending outwardly from the flange  66  toward a part cylindrical insert  81  carried within a part cylindrical receptacle  82  for pivotal movement relative thereto about an axis  83 . 
     A part of the receptacle  82  engages over the flange  51  and the web  50  and is received within the angle therebetween. The receptacle  82  is attached to a drip rail  84  by a web portion  85  projecting upwardly from an uppermost edge of the part cylindrical receptacle  82 . The drip rail  84  includes an exterior flange  86 , a base  87  and an interior flange  88  attached against the surface  12 A and fixed thereto by screws  89  and a structural adhesive. 
     A bottom edge of the coping panel  24  engages over the flange  88  so as to act as a water shedding arrangement which is more clearly described in and forms part of the subject matter of one of the above co-pending applications, the disclosure of which is incorporated herein by reference. 
     The bottom edge of the part cylindrical receptacle  82  is indicated at  90  and the connector  80  includes a U-shaped portion  92  which wraps around the portion  90 . Thus the receptacle  82  encloses the part cylindrical insert  81  sufficiently to hold it in place in the closed position shown in FIG.  3 . 
     As shown in FIG. 4, the pane structure  56  can be pivoted about the axis  83  from the vertical position shown in FIG. 3 to the horizontal shown in FIG. 4 where the U-shaped portion  92  reaches the web  85 . In this position it will be noted that the part cylindrical insert  81  can be pulled horizontally out of the part cylindrical receptacle  82  since the bottom edges  81 A and  81 B of the insert can clear the edge  90  of the receptacle. In this way the pane structure can be removed for replacement or service. 
     In order to prevent the window from being removed except when properly required by service personnel, a locating piece  93  is inserted into each end of the part cylindrical insert  81  and bonded in place so as to define a stub shaft  94  projecting outwardly beyond the end of the part cylindrical insert at the respective side of the pane structure as shown in FIG.  5 . This stub shaft portion  94  is thus exposed beyond the end of the pane structure and defines an outside cylindrical surface matching that of the interior of the receptacle  82 . A removal prevention block  95  is mounted at the stub shaft  94  on the web  85  and fills the space between the stub shaft and the underside of the base  87  of the drip rail  84 . Thus, with the removal block  95  in place held by bolts  96 , the window can be pivoted to the open position shown in FIG. 4 but cannot be removed unless the block  95  is first removed. The block  95  is held in place by a bolt  96  passing through the block and into the web  85 . The bolt is removed only by authorized personnel allowing the pane structure to be removed. The window can be pivoted to the open position shown in FIG. 4 as a safety exit in the event that exit through the conventional doors is prevented or inhibited. 
     Turning now to FIGS. 8,  9  and  10  there is shown the latching arrangement by which the pane structure  56  is held in the closed position during normal operation. The latching arrangement includes a pair of latches both located in the bottom frame member adjacent the sides. Each latch  97  includes a pin  99  standing upwardly from the bottom pan member and a latch assembly  98  is mounted within the hollow interior  58  of the bottom frame member of the pane structure  56 . The latch assembly  98  is operable from inside the vehicle for releasing the bottom part of the pane structure for pivotal movement to the open position for emergency exit. 
     The pin  99  includes a bottom threaded section which engages a washer  100 , passes through the web member of the pan, engages a washer  101  and enters a hole  102  in the rail of the frame across the bottom of the window opening. An upper part of the pin passes through a slot  103  in the frame member  56  as the pane structure  56  is moved to the closed position. The latch assembly  98  inside the bottom frame member includes a pair of fingers  104  and  105  defining a recess  107  which the receives the pin  99 . 
     The jaw including the fingers  104  and  105  is pivotally mounted on a pin  108  carried in a channel-shaped insert  109  inserted into the hole  103 . Thus a top wall of the channel-shaped member  109  inserts underneath a top wall of the frame member and a bottom wall of a channel member sits on top of the bottom wall of the frame member. 
     In the open position shown in FIG. 10, the pin can slide into the open mouth of the recess  107  between the fingers  104  and  105 . In the closed position shown in FIG. 9, the jaw pivots about the pin  108  so that an inside surface of the jaw  104  abuts against the pin and pulls the frame toward the interior of the window pane thus providing a cam action on the pin. 
     The jaw is pivotal around the pin  108  and is driven in the pivotal movement by a bell crank  110  pivotal about a pin  111  also mounted in the C-shaped member  109 . The bell crank  110  and the jaw are spring biased by springs wrapped around the respective pivot pins. 
     The bell crank  110  is actuated by a rod  112  extending inside the frame longitudinally of the frame and movable along its length. 
     The rod  112  is actuated in its longitudinal movement by a bell crank  113  mounted for pivotal movement on a pin  114  carried on a mounting plate  115 . The mounting plate is mounted within the frame member so that it is fixed relatively thereto and thus acts to hold the end of the rod so the rod is supported in position longitudinally of the frame member. 
     The bell crank  113  has a portion on top of the plate  115  and a further portion which extends down below the plate  115  where it carries the end of the rod  112 . The portion of the bell crank  113  above the plate  115  carries an upstanding actuating plate  116  which projects to one side of the pivot pin  114  so that rearward pushing movement against the plate  116  acts to pull the rod away from the bell crank  110  thus causing the bell crank to pivot about its pin  111  and causing the jaw to move to the open position. 
     The latching assembly  98  forms one of a pair of symmetrical latching assemblies each arranged adjacent a side edge of the bottom frame member of the window frame structure. An actuating handle  118  is mounted on a pivot shaft  119  carried on a pair of brackets  120  and  121 . The brackets  120  and  121  are carried on the inside surface of the interior cladding  175  so as to locate the pivot shaft  119  above the frame member of the bottom of the pane structure. The handle  118  follows the curvature of the curved portion  177  of the cladding and has side edges abutting ends  123 ,  124  of the cladding at an opening in the cladding. The handle thus provides a smooth attractive appearance contiguous with the cladding. A break  125  in the grill  179  provides an opening into which the fingers of the user can be inserted to pull on a top edge  126  of the handle, pulling the handle downwardly so that a bottom lug  127  of the handle underneath the pivot shaft  119  pushes against the plate  116  to move the bell cranks  113  from the closed position shown in FIG. 9 to the opened position shown in FIG.  10 . 
     Thus the single handle at the center of the window pane structure actuates both of the latches simultaneously releasing the latches for the pane structures to be pivoted outwardly as previously described. The handle  118  is spring biased by a spring  128  on the pivot shaft  119  to hold the handle in the closed position. 
     Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.