Abstract:
A process of retrofitting an existing window that uses a gasket to secure a sacrificial member and a glazing. The sacrificial member forms a replaceable protective barrier between the glazing and occupants of a vehicle such as a bus. The gasket is traditionally used to secure the sacrificial member and the glazing to the window. Over time, after several removal and re-installations during replacement of the sacrificial member or the glazing, the gasket typically becomes unfit for subsequent use. The gasket is replaced with a rigid retainer member that fits into an existing recess that receives the gasket. The retainer member secures the sacrificial member and the glazing to the window so as to permit repeated changes of the sacrificial member without removal of the retainer member.

Description:
RELATED APPLICATIONS 
   This application is a continuation of U.S. patent application Ser. No. 10/142,807, filed on May 9, 2002, now U.S. Pat. No. 7,082,736 entitled “PROCESS FOR RETROFITTING AN EXISTING BUS WINDOW HAVING RUBBER SEALS WITH METAL MEMBERS THAT DEFINE A RETENTION SPACE FOR A SACRIFICIAL MEMBER,” which is a continuation in part of U.S. patent application Ser. No. 10/057,617, filed Jan. 23, 2002 entitled “Quick Release Sacrificial Shield for Window Assembly” now U.S. Pat. No. 6,688,044, issued Feb. 10, 2004, which was a continuation of U.S. patent application Ser. No. 09/395,692 filed Sep. 13, 1999, entitled “Quick Release Sacrificial Shield For Window Assembly” now U.S. Pat. No. 6,408,574, issued Jun. 25, 2002, which was a continuation-in-part of U.S. patent application Ser. No. 09/186,513, filed Nov. 4, 1998, entitled “Quick Release Sacrificial Shield For Window Assembly” now U.S. Pat. No. 6,205,723, issued Mar. 27, 2001. This application also claims the benefit of U.S. Provisional Application No. 60/290,136, filed on May 9, 2001, entitled “PROCESS FOR RETROFITTING AN EXISTING BUS WINDOW HAVING RUBBER SEALS WITH METAL MEMBERS THAT DEFINE A RETENTION SPACE FOR A SACRIFICIAL MEMBER.” 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to windows for mass transit vehicles and, in particular, concerns an apparatus and method for reconfiguring bus windows so as to replace rubber retention members with metal retention members that define a space to receive a sacrificial layer. 
   2. Description of the Related Art 
   Mass transit vehicles, for example buses and trains and the like, typically have a plurality of windows positioned adjacent the seats of the mass transit vehicles. One difficulty that mass transit vehicle operators experience is that passengers sitting inside the mass transit vehicle will often use sharp objects to scratch the glazing of the window thereby damaging the appearance of the window. Over time, mass transit vehicles, particularly those used in large urban areas, can have windows that are significantly obscured with scratched glazings that may contain offensive comments and slogans. Replacement of the glazing can be a particularly expensive proposition given the difficulty of removing the glazing from the window and the expense of purchasing a replacement sheet of glazing that is specifically sized to meet the contours of particular window opening of the mass transit vehicle. 
   To address this particular need, sacrificial layers are often positioned at the inner surface of the glazing wherein the sacrificial layer is interposed between the rider of the mass transit vehicle and the inner surface of the glazing. Typically, the sacrificial layer is a layer of inexpensive acrylic or plastic that can be more easily removed and replaced than the underlying glazing. Hence, users who would otherwise attempt to damage the glazing end up damaging the sacrificial layer that can then be easily replaced. 
   One common mechanism for retaining the sacrificial layer is to position a rubber gasket in the window frame so as to extend around the periphery of the opening of the window frame. This gasket can then define a space into which the edges of the sacrificial layer can be positioned so as to retain the sacrificial layer adjacent the glazing. Such a gasket also retains the glazing of the window within the frame. Thus, when the sacrificial layer and/or the glazing of the window is to be replaced, the rubber gasket needs to be removed from the frame. After the sacrificial layer and/or the glazing of the window is replaced, the gasket, frequently a new set, is repositioned in the window frame. 
   One difficulty with the use of such a rubber retainer is that replacement of the rubber can be a very time consuming and costly endeavor. In particular, the rubber retainer must be removed from the window frame, and over time such rubber retainer can no longer be used. Consequently, a new rubber retainer must then be installed into the window frame to replace the damaged rubber retainer. Installation of such a rubber retainer is often a very difficult and time consuming process which is even more exacerbated by the fact that most mass transit vehicles have multiple windows that require multiple retainers. 
   Hence, there is an ongoing need for window protectors and, in particular, sacrificial window protectors that can be more easily replaced at a reduced cost. To this end, there is a need for a reusable retainer for use in conjunction with the sacrificial layers. 
   SUMMARY OF THE INVENTION 
   The aforementioned needs are satisfied by a method of retrofitting an existing window in a mass transit vehicle with a replacement sacrificial member retention assembly. The method comprises extracting a rubber gasket from a recess formed in the frame of the window so that the rubber gasket no longer retains the sacrificial member adjacent a first side of a glazing of the window. The rubber gasket also no longer retains the glazing in the frame. The method further comprises sizing a rigid retainer such that the rigid retainer can be positioned in the recess. The method further comprises positioning a plurality of rigid retainers into the recess in the frame such that the rigid retainers are able to retain the sacrificial member adjacent the first side of the glazing. The rigid retainers are also able to retain the glazing in the frame. The method further comprises positioning a sacrificial member adjacent the first side of the glazing so as to be retained by the rigid retainers. 
   One implementation of the method further comprises, prior to positioning a plurality of rigid retainers, positioning a replacement glazing in the frame. The rigid retainer preferably comprises a first leg sized to fit into the recess in the frame, and a second leg that defines a space sized to receive the sacrificial member such that the sacrificial member is secured adjacent the first side of the glazing. The second leg retains the glazing in the frame by engaging the portion of the first side of the glazing. The space defined by the second leg is dimensioned such that the edges of the sacrificial member slide within the spaces of the rigid retainers positioned at opposite sides of the frame so as to facilitate removal and positioning of the sacrificial member. In one embodiment, the second leg is further adapted to permit a fastener to extend into the space so as to inhibit sliding of the sacrificial member. 
   The rigid retainer positioned in the recess in the frame remains in place when the sacrificial member is replaced. The rigid retainer is formed from a resilient material to permit repeated use as sacrificial member is replaced repeatedly, and in one embodiment the rigid retainer is formed from a metal. Such rigid retainer is used to retrofit a mass transit vehicle such as a bus. 
   Another aspect of the invention relates to a method of replacing a sacrificial member of a window in a mass transit vehicle. The method comprises removing a rubber gasket from a recess formed in a frame of the window so that the rubber gasket no longer retains the sacrificial member adjacent a first side of a glazing of the window. The method further comprises removing the existing sacrificial member from the first side of the glazing. The method further comprises substituting the rubber gasket with at least one rigid retainer that is dimensioned to fit into the recess in the frame of the window and retain the sacrificial member adjacent the first side of the glazing. The method further comprises installing a new sacrificial member such that the at least one rigid retainer retains the new sacrificial member adjacent the first side of the glazing. 
   The rigid retainer preferably comprises a first leg sized to fit into the recess in the frame and a second leg that defines a spaced sized to receive the sacrificial member such that the sacrificial member is secured adjacent the first side of the glazing. The space defined by the second leg is dimensioned such that the edges of the sacrificial member slides within the spaces of the plurality of rigid retainers positioned at opposite sides of the frame. 
   Installing the new sacrificial member comprises sliding the upper edge of the sacrificial member into the space of the at least one rigid retainer positioned at the top of the frame so as to facilitate positioning of the lower edge of the sacrificial member into the space of the at least one rigid retainer positioned at the bottom of the frame. In one embodiment the second leg is further adapted to permit a fastener to extend into the space so as to inhibit sliding of the sacrificial member. 
   The rigid retainer is formed from a resilient material to permit repeated use as sacrificial member is subsequently replaced repeatedly, and in one embodiment the rigid retainer is formed from a metal. Such rigid retainer is used to replace the sacrificial member of the window in mass transit vehicles such as a bus. 
   Yet another aspect of the invention relates to a method of replacing a glazing of a window in a mass transit vehicle. The method comprises removing a rubber gasket from a recess formed in a frame of the window so that the rubber gasket no longer retains the glazing in the frame. The method further comprises removing the glazing from the frame, and installing a new glazing in the frame. The method further comprises substituting the rubber gasket with at least one rigid retainer that is dimensioned to fit into the recess formed in the frame and retain the glazing in the frame. 
   In one implementation, the method further comprises, after substituting the rubber gasket, installing a sacrificial member adjacent the glazing such that the sacrificial member is also retained by the at least one rigid retainer. In one embodiment, the rigid retainer comprises a first leg sized to fit into the recess in the frame and a second leg adapted to retain the glazing in the frame. The rigid retainer is formed from a resilient material to permit repeated use as glazing is subsequently replaced repeatedly. In one embodiment, the rigid retainer is formed from a metal, and such rigid retainer is used in mass transit vehicles such as a bus. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a typical bus that exemplifies a common mass transit vehicle; 
       FIG. 2A  illustrates a typical window assembly found on mass transit vehicles such as the bus of  FIG. 1 ; 
       FIG. 2B  illustrates a cross sectional view of a frame of the window assembly showing how a sacrificial member is traditionally mounted adjacent a glazing; 
       FIG. 3  illustrates a manner in which the sacrificial member is traditionally replaced; 
       FIG. 4  illustrates a cross sectional view of the frame showing retrofitting of the window assembly with a retention member that retains the sacrificial member and the glazing; 
       FIG. 5A  illustrates a cross sectional view of the bottom portion of the frame showing the retrofitted window assembly; 
       FIG. 5B  illustrates a cross sectional view of the top portion of the frame showing a space defined by the retention member dimensioned so as to permit improved replacement of the sacrificial member; and 
       FIG. 6  illustrates one embodiment of the retrofitted window assembly with a plurality of retention members positioned at selected locations. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Reference will now be made to the drawings wherein like numerals refer to like parts throughout.  FIG. 1  illustrates a bus  101  that exemplifies a common mass transit vehicle. The bus  101  comprises a plurality of windows  100  positioned at selected locations on side panels  103 . Each window  100  comprises a glazing  104  mounted on a frame  102 . It is common for the window  100  to further comprise a sacrificial member  106  that protects the glazing  104 . 
     FIG. 2A  illustrates an isolated view of one typical window  100  that might be found on mass transit vehicles such as the bus  101  of  FIG. 1 . The window  100  comprises the glazing  104  mounted on the frame  102 . The window  100  may further comprise a sacrificial member  106  that forms a layer adjacent to the glazing  104 , so as to provide a replaceable protective barrier between the glazing  104  and occupants of the vehicle. As is known in the art, windows in mass transit vehicles are subjected usual wear and tear as well as acts of intentional vandalism. The replaceable sacrificial member  106  protects the more costly glazing  104  from such mistreatments. Traditionally, the sacrificial member  106  is secured to the window  100  by a gasket  110  in a manner described below. One type of the costly glazing  104  is approximately ¼″ thick, and one type of the sacrificial member  106  is less than ⅛″ thick. 
     FIG. 2B  illustrates a cross sectional side view of the frame  102 , showing the glazing  104  mounted in the frame  102  with an external seal member  112  interposed therebetween. The seal member  112  seals out the exterior of the vehicle from the interior of the vehicle in a manner well known in the art. 
   The sacrificial member  106  is positioned in a layer adjacent a first side  108  of the glazing  104 , and is secured in place by the gasket  110  that is pressed into a recess  114  defined by the frame  102 . The gasket  110  is selected so as to permit it to securely hold the sacrificial member  106  in place. The gasket  110  may be secured in place either by frictional fit, or by an adhesive. The gasket  110  also retains the glazing  104  in the frame  102  adjacent the seal member  112 . 
     FIG. 3  illustrates the traditional method of replacing the sacrificial member  106 , wherein the gasket  110  is removed from the frame  102  so as to permit the sacrificial member  106  to be removed. As is well known in the art, once a gasket is removed from its fixed configuration of extended time, it loses some of its usefulness. Thus after several use over time, the gasket  110  may become brittle and cracked, rendering it unsuitable for further use. As a result, the gasket  110  typically needs to be replaced regularly, thus adding to the cost of time and material associated with the procedure. Since the gasket  110  also retains the glazing  104  in the frame  102 , the gasket  110  needs to be removed when the glazing  104  is replaced. This further increases the cost of window maintenance when such gaskets are used. Aside from the material cost of the gasket, re-installing the gasket is labor-intensive, thus further adding to the cost of window maintenance. 
     FIGS. 4 ,  5 A and  5 B illustrate a process for retrofitting the window  100  so as to remove its dependence on the gasket  110  to secure the sacrificial member  106  and the glazing  104  in place. After the gasket  110  is removed from the frame  102 , as described above in reference to  FIG. 3 , a retainer member  120  is inserted into the recess  114  that was previously occupied by the gasket  110 . As shown in a cross sectional view in  FIG. 4 , one embodiment of the retainer member  120  comprises a first leg  122  and a second leg  124 . The first leg  122  is sized to fit into the recess  114  that previously received the rubber gasket  110 , and the second leg  124  is spaced outward from the first leg  122  so as to define a space  132  into which a sacrificial member  106  can be positioned adjacent the first side  108  of the glazing  104 . 
   In one embodiment, the first leg  122  has a rounded end  126  so as to facilitate easier insertion into the recess  114 . The first leg  122  further comprises a plurality of serrations  130  that helps to secure the first leg  122  in the recess  114 . In one embodiment, the retainer member  120  further defines various openings  134  that can receive additional seals and the like. 
   Preferably, the retrofitting of the window  100  is performed when the sacrificial member  106  is replaced. It will be appreciated, however, that the retrofitting of the window  100  can be performed at any time without departing from the spirit of the invention. 
     FIG. 5A  illustrates a cross sectional view of a retrofitted window  100 , wherein the retainer member  120  has replaced the gasket  110  described above in reference to  FIGS. 2 and 3 . The first leg  122  engages the frame  102  such that the sacrificial member  106  can be received into the space  132  defined by the second leg  124 , and held therein securely adjacent the first side  108  of the glazing  104 . 
   As shown in  FIG. 5A , the sacrificial member  106  is retained in place adjacent the first side  108  of the glazing  104  by one embodiment of a first seal  146  mounted in the openings  134  defined by the second leg  124 . In particular, the first seal  146  engages the portion of the sacrificial member  106  and pushes it against the first side  108  of the glazing  104 . Furthermore, the cross section of the first seal  146  defines a wedge whose tip engages the first side  108  of the glazing  104 , thus retaining the glazing  104  securely adjacent the seal member  112 . A portion of the wedge defined by the first seal  146  engages the edge of the sacrificial member  106  and inhibits the sacrificial member  106  from sliding beyond the first seal  146 . In one embodiment, the first seal  146  is made from resilient rubber or hard vinyl so as to provide sealing and retaining properties in a reusable manner. 
     FIG. 5B  illustrates another retainer member  140  that is similar to the retainer  120  described above. The retainer member  140  comprises a first leg  142  and a second leg  144 , wherein the second leg  144  is adapted to permit a fastener  152  to extend into a space  150  defined by the second leg  144 . The retainer member  140  is positioned on the opposite side from the retainer member  120  in order to permit the sacrificial member  106  to be installed and removed from the window in a manner similar to the process disclosed in a co-pending Provisional Application by Farrar titled “Sacrificial shield for window assembly”, Ser. No. 09/820,184, filed on Mar. 27, 2001. The sacrificial member  106  is sized such that when installed, the fastener  152  extending into the space  150  inhibits the sacrificial member  106  from moving while occupying a portion of the space  150 . To remove the sacrificial member  106 , the fastener  152  is retracted from the space  150  so as to permit the sacrificial member  106  to slide into the rest of the space  150 , thus freeing the other edge of the sacrificial member  106  from the space  132  described above in reference to  FIG. 5A . 
     FIG. 5B  further illustrates one embodiment of a second seal  148  mounted in openings  160  defined by the second leg  144 . In particular, the second seal  148  engages the portion of the sacrificial member  106  and pushes it against the first side  108  of the glazing  104 . Furthermore, the cross section of the second seal  148  defines a wedge whose tip engages the first side  108  of the glazing  104 , thus retaining the glazing  104  securely adjacent the seal member  112 . It will be appreciated that the process of retrofitting the portion of the window with the retainer member  140  is substantially similar to the process described above in reference to the retainer member  120 . It will further be appreciated that other procedures (than that disclosed in Provisional application Ser. No. 09/820,184) may be employed to install and remove the sacrificial member  106  from the window  100  without departing from the spirit of the invention. 
     FIG. 6  illustrates an exemplary embodiment of the retrofitted window  100  comprising the retainer members  120  being positioned on the opposite sides of the retainer members  140  so as to permit installation and removal of the sacrificial member  106  as described above. In another embodiment of the retrofitted window  100 , the retainer member  140  of  FIG. 5B  is substantially same as the retainer member  120  of  FIGS. 4 and 5A . The window is retrofitted such that the retainer member positioned at the bottom of the window is fitted with the first seal  146  as described above in reference to  FIG. 5A , and the retainer members positioned at the top and sides of the window are fitted with the second seal  148  described above in reference to  FIG. 5B . 
   It will be appreciated that the retrofitted window  100  permits subsequent changes of the sacrificial members  106  to be performed in an easier manner. Furthermore, the retrofitted window  100  permits replacing of the glazing itself when necessary (such as when the glazing is damaged) in an improved manner described above. In one embodiment, the retainer members  120 ,  140  are formed from a resilient material such as plastic or vinyl so as to permit repeated use, thus providing cost savings by not discarding the traditional gaskets described above. 
   Although the foregoing description of the preferred embodiment described and pointed out the fundamental features of the invention, it will be understood that various omissions, substitutions and changes in the form of the detail of the apparatus and method as illustrated, as well as the use thereof, may be made by those skilled in the art, without departing from the spirit of the present invention.