Abstract:
The present invention is a barrier shield having selective transparent areas therein that incorporates particular optical glare and reflection reduction methods utilizing diffractive and grating techniques within a tilted planar surface having selective openings therethrough. This barrier shield is mounted within the closure door for correcting the transmissive optical imagery enabling the driver/operator to view the passengers through the closure door barrier shield using, typically, the inside rear-view mirror without compromise to safety or security.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This patent application incorporates by reference provisional patent application 60/525,789, filed Nov. 29, 2003, titled “Anti Glare Passenger Bus Barrier Shield” and this is the regular utility patent application of this provisional patent application. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to passenger buses and the like, and, in particular, relates to devices to prevent passengers from interfering with the driver, and, in greater particularity, relates to doors that act as a barrier shield to the passenger area of the bus, as drivers now face heightened security issues. 
   2. Description of the Prior Art 
   Intercity passenger buses may be used to transport passengers from point to point such as Greyhound buses. Similar buses may also be used in mass transit operations within a metropolitan area. In any event, the bus driver is normally preoccupied with driving the bus and thus may be unaware of passengers attempting to assault the bus driver, take over the bus or attempting to crash the bus until it is too late to prevent direct contact and is thus unable to defend himself/herself without possibly crashing the bus because of the interference from the attacking passenger(s). If the passenger bus is a mass transit bus, a passenger may be attempting to rob the driver of collected fares also. 
   Buses are typically operated during all times of the day, but night time operations creates special problems for the driver. The driver is confronted with glaring lights and reflections from lights, from vehicles in the rear and those approaching, so it is difficult for the driver to monitor the passenger area by looking in the inside rear-view mirror. Interior lights also create glare and reflections as well as sun light during the day time. 
   Several issued patents are directed at devices for protecting the driver from attacking passengers. 
   U.S. Pat. No. 4,227,735 issued on Oct. 14, 1980 and entitled “Protective Enclosure for a Bus” discloses an enclosure about the driver of a typical mass transit bus. The driver&#39;s location is surrounded by a rear wall with transparent windows therein and a side wall also with transparent windows therein. A fare collecting device may be attached to the side wall. The side wall also contains a locking door with transparent windows therein. Although glass may be one type of transparent material there are other types of materials that will present an impenetrable transparent window such as clear polycarbonate materials. The windows in this patent are vertical and thus would not provide the driver with glare and reflection prevention. 
   U.S. Pat. No. 5,004,286 issued on Apr. 2, 1991 and entitled “Transport Vehicle Protective Shield” discloses a compartment for the bus driver having transparent, multi-layered, bullet-proof paneling. All of the paneling is vertically oriented and thus would present glare and reflections to the driver. 
   U.S. Pat. No. 5,647,629 issued Jul. 15, 1997 and entitled “Reflection Eliminator” discloses a structure having a plurality of vertically oriented members. The device is typically placed on the dash, for example, and prevents sun light from being reflected off of the dash onto the sloping window and then into the eyes of the driver. The use of this device to prevent glare and reflections from vertical windows such as in the enclosure/compartment shown above is not feasible. 
   Even when there is a security isolation booth structure as disclosed in the first two patents, the driver/operator of a bus has difficulty viewing passengers while using the inside rear-view mirror. A closure door may be designed to open and latch against a panel installed on the right side of the aisle while the bus is in operation. In order for the driver to see the passenger area through the closure door, typically, a transparent vertical insert is placed in the closure door. The driver/operator is unable to observe or observe with great difficulty the passengers while using the inside rear-view mirror because of daytime and nighttime optical glare and reflection projected off the flat vertical insert of the closure door thus posing a safety and security dilemma. 
   Further anti-glare and anti-reflection techniques, both required in the present invention, such as screens, films, coatings, and surface-changing processes are more limited to particular surfaces and images. The desired image is usually in near proximity to the surface of glare and reflection in order for any of the above techniques to be successful, as opposed to desired images of a distant proximity from a surface of glare and reflection because of the dispersion of light rays versus the transmission of light rays. The need to view distant images through a surface of glare and reflection created a situation where existing methods could not achieve their intended purpose. 
   Thus, there exists a need for bus driver barrier shield that allows the bus driver to protect himself/herself from attack while at the same time allows the viewing of the passenger area by an inside rear-view mirror or directly by substantially reducing or eliminating the glare and reflections from the barrier shield itself. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention provides a driver/operator with an isolation enclosed structure built within the bus for driver security. A barrier shield is specifically installed within a frame of a closure door so as to maintain the integrity of the security surround and reduce or eliminate optical glare and reflection. 
   The present invention is a barrier shield having selective transparent areas therein that incorporates particular optical glare and reflection reduction methods utilizing diffractive and grating techniques within a slanted insert having selective openings therethrough. This barrier shield is mounted within the closure door for correcting the transmissive optical imagery enabling the driver/operator to view the passengers through the closure door barrier shield using, typically, the inside rear-view mirror without compromise to safety or security. 
   The barrier shield for use in multiple passenger vehicles like buses is installed in the closure door located adjacent the driver of the bus. The barrier shield may be rotated to block the passenger isle of the bus. The barrier shield has an apertured area having one or more predetermined openings therein for increased visibility. These opening may be horizontal slots or other types of openings. The apertured area is a part of a high visibility insert which has a slant ranging from zero degrees to about 10 degrees, preferably about 6 degrees. The high visibility insert is composed of a transparent material, preferably polycarbonate. The high visibility insert may be a part of a back panel. The back panel being composed a substantially flat transparent material and having the apertured area and the high visibility insert therein is mounted in the closure door. 
   One objective of the present invention is to provide a barrier shield that allows the driver/operator increased visibility of the passengers without compromising safety, security, or the design of the driver&#39;s isolation enclosure structure. 
   Another object of the present invention is to provide for a transparent glare-reducing shield for installation in a passenger bus with little or no modification to the isolation booth or its closure door. 
   Another object of the present invention is to provide for a barrier shield having similar transparent materials as materials used in other parts of the isolation booth to achieve anti-glare and anti-reflection qualities. 
   A further object of the present invention is to provide a barrier shield of a decorative design to reduce or eliminate the fears and anxieties of the passengers who further will be looking through the barrier shield in the direction of travel of the bus. 
   These and many other objects, features and advantages of the present invention will be readily apparent to one skilled in the pertinent art from the following detailed description of a preferred embodiment of the invention and the related drawings. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  is front elevational view of the barrier shield of the present invention; 
       FIG. 2  is a front elevational view of the barrier shield of the present invention installed in an enclosure door frame, a closure door being in the open position about the driver&#39;s position on a conventional bus, only partially shown; 
       FIG. 3  is a front elevational view of another embodiment of the barrier shield of the present invention having more slots than the barrier shield shown in  FIG. 1 ; 
       FIG. 4  is a top view of the barrier shield of  FIG. 3  tilted backward by about 30 degrees; 
       FIG. 5  is a bottom view of the barrier shield of  FIG. 4 ; 
       FIG. 6  is a right side cross sectional view of the barrier shield of  FIG. 3 ; 
       FIG. 6A  illustrates in greater detail the slots having an upper and a lower wall perpendicular to the vertical direction of the enclosure door of the present invention. 
       FIG. 7  is a front side perspective view of the barrier shield of  FIG. 3 ; 
       FIG. 8  is a perspective view of the securing means for placing the barrier shield across the isle of the bus in a closed position; and 
       FIG. 9  is a partial front elevational view of one embodiment of securing means for securing the barrier shield in the closure door frame. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIG. 1 , a barrier shield  10  is shown by a front elevational view removed from a closure door  12  of  FIG. 2 . As seen in  FIG. 1 , the preferred embodiment of the present invention is an integrally formed transparent plastic barrier shield  10 . The barrier shield  10  comprises a slanted high visibility insert  14  with an apertured area  88  having at least one or more openings therein with predetermined shapes such as a grate area with a plurality of horizontal slots therein such as shown in the  FIG. 3 , for example. Attachment means  18  such as bolt holes are positioned about mounting flanges  16  to be discussed below. A latch mounting area  23  being an extended panel section is positioned on the bottom of the barrier shield  10 . The slanted high visibility insert  14  has a plurality of predetermined openings  20  as seen in  FIG. 1 , approximately 8 to 15 horizontal viewing ports or slots  22  which span the width of the slanted high visibility insert  14 . As seen in  FIG. 1 , the dashed lines  86  indicate bend lines in a panel  17  in which attaching walls  19  are formed between the flanges  16  and the slanted high visibility insert  14  as to be further detailed herein. 
   The operating environment of the barrier shield  10  in the closure door  12  is clearly shown in  FIG. 2 . As seen therein, the closure door  12  is in the open condition, blocking entrance to a driver seat. 
   As seen in  FIG. 1 , the barrier shield  10  is made from one piece of molded thermoforming plastic such as a polycarbonate material. As seen therein, all edges, corners, and junctions of walls are rounded in the molding process to present a professional appearance as well as providing non-cutting edges to passengers including especially child who pass by the opened closure door  12  as seen in  FIG. 2 . The slots  22  may be formed as an integral part of the molding process or formed in a router process. Although the preferred material is polycarbonate, other materials may be used which are acceptable in the manufacturing process as well as compatible with other viewing areas near the driver isolation enclosure structure  24 , only partial seen in  FIG. 2 . Glass may be considered but it is more difficult to form into the shapes shown and would be a heavier, more expensive material. Considering the proximity of the barrier shield  10  to passengers, the surfaces must be easily cleaned and resistant to scratches, cuts, chips, etc. Further, the material must be sufficiently thick and strong to prevent breakage from accidental hits from luggage and other carry-on objects. Polycarbonate is an ideal material in that it is very strong and shatter proof in the present environment and conforms with regulatory standards. 
   The barrier shield  10  as shown is totally composed of a clear transparent material. Although parts of the barrier shield  10  may be partially colored or of a solid color, the preferred color is clear water. The preferred barrier shield  10  is integrally formed of plastic material, but the barrier shield  10  may be made of separate parts secured together to form a similar structure. Having the barrier shield  10  made of a clear material presents to the passengers a less threatening structure and a more open structure so that they can clearly see the bus driver and see in the direction of the bus travel as compared to a solid door with only the clear insert therein. 
   The barrier shield  10  may be constructed of various pieces of plastic material so that when glued or otherwise secured to the other pieces, the joints will be squared off and the edges will be sharp. This would further require rounding of the sharp angular edges and an increase in the manufacturing costs. 
   As seen in  FIG. 2 , the barrier shield  10  is mounted to a closure door frame  42 . As a preferred material, the door frame  42  is made from stainless steel tubing so as to present a professional appearance and a relatively maintenance free material. The only welded joints in the door frame  42  are covered by corner caps  44  which simultaneously provide a mounting surface for the upper and lower hinges  38  and  40 , respectively. 
   The barrier shield  10  may be mounted to the door frame  42  by various techniques. Referring to  FIG. 2 , mounting channels could be attached to the inside of the door frame  42  and the edges of the flanges  16  of the barrier shield  10  would be placed therein and secured by adhesive and/or nuts and bolts, not shown. 
   As seen in  FIG. 9 , the barrier shield  10 , only partially shown, being on the outer corner of the closure door  12 , as noted in  FIG. 2  by a view IX, is secured by means of tube clamps  68  to the door frame  42 . Bolt holes are drilled in the barrier shield  10  for the placement therein of nut and bolts hardware  76  through the tube clamps  48  and the flange  16 . All metal materials in the closure door  12  are preferably stainless steel unless otherwise noted. 
   As seen in  FIG. 2 , closure door  12  is mounted by hinges  38  and  40  to a vertical door support  36 . The vertical door support  36  is attached to a vertical enclosure support  34  by means of a locking fixture, not shown, or by nut and bolts. The vertical enclosure support  34  provides partial support to the isolation enclosure structure  24 , seen only partially in  FIG. 2 . The isolation enclosure structure  24  surrounds a driver seat  26  on the back side, to the left and right sides. The upper enclosure section  48 , is normally composed of a clear, solid formed design, preferably polycarbonate, as opposed to multiple window pieces. It is intended that the barrier shield  10  be made of similar materials as the surround in the upper enclosure section  48 . The lower enclosure section  50  being of similar shape as the upper enclosure section  48  is normally composed of a panel of material such as plastic or metal. 
   A steering wheel  28  is conventionally located in front of the driver seat  26 . The bus has a front windshield  30  and a side window  32 . 
     FIG. 2  shows the closure door  12  in the open position and blocking entrance to the driver seat  26  and the related area. This is the position of the door  12  when passengers are entering the bus. The driver would be standing near the door  12  or adjacent to the entry door of the bus, not shown, to check passengers into the bus. After the passengers are loaded, the bus driver will turn the closure door  12  approximately 90 degrees to the left to a closed position as only partially seen in  FIG. 8 . 
   A securing device  52  is further shown in  FIG. 8  in greater detail. 
   Clearly many devices may be used to secure the closure door  12  to an entrance panel  54 , also known as, a passenger modesty panel, like with magnets and the following description is merely to show one type of mechanism for attaching the closure door  12  to the entrance panel  54 . 
   In  FIG. 8 , a male latch device  56  is shown as a cylindrically shaped section  60  with an attaching neck  62  on a base  64 . The base  64  may be secured to the barrier shield  10  or door frame  42  by bolts and nuts, for example. 
   A female latching device  58  is composed of a pair of flexible wings  70  and  72  having inwardly protruding sections attached to a base  74 . The cylindrically shaped section  60  when sufficiently urged will enter into and spread apart the wings  70  and  72  and will be held within the wings  70  and  72  by the inwardly protruding sections. 
   It is therefore seen that the closure door  12  may be opened even by the passengers by pushing against the door  12 . This allows safe exit in case of an emergency when the driver is unable to assist due to injury or death or otherwise. 
   It is therefore necessary that the driver have a very clear view into the passenger area of the bus so as to observe passenger movement. A passenger attempting to reach the driver would have to push open the closure door  12 , but this would provide a measure of protection to the driver since the closure door  12  partially blocks access to the driver when in the open position as seen in  FIG. 2 . 
   Referring to  FIG. 3 , the barrier shield  10  is shown by an elevational front view. The dashed lines refer to bend lines in the plastic panel. The solid lines are wall edges. As seen in  FIG. 2  and  FIG. 3 , the flanges  16  about the slanted high visibility insert  14  are used to secure the barrier shield  10  to the door frame  42 . Although the flanges  16  may not be used, the means for attaching the slanting high visibility insert  14  becomes more difficult although clearly within the skill of a person in the art. The latch mounting area  23  shown in  FIG. 1  is used for the placement thereon of certain items such as the securing device  52 . The slanted high visibility insert  14  is attached to the flanges  16  by two triangular shaped walls  78  and a top rectangular wall  80 . A slanted back panel  82  of plastic, for example, is attached to the three walls,  78  and  80 . The bottom  84  of the back panel  82  is attached to the flange  16  at the bottom. If the insert  14  is an integrally formed piece of plastic, for example, all of the joints between the walls  78  and  80  and the slanted back panel  82 , the latch mounting area  23  and the flanges  16  are clear solid plastic. The bend lines  86  are merely placed on the drawings for assistance in understanding the structure of the barrier shield  10 . 
   The horizontal viewing ports  22  forming an apertured area  88  are typically rectangular openings as seen in  FIG. 6  in cross section and formed after the molding process and cut out at a later time during manufacturing. The slots  22  may number between 8 and 15 and are typically 0.50 inches high, about 9 inches long, and area approximately 0.375 inches deep through the panel  82 . The slots  22  are about 0.50 inches apart. See also  FIG. 6A . The slanted back panel  82  and walls are approximately 0.375 inches thick also. The extent of the high visibility insert  14  is indicated by the extension lines on the right side. This is further shown in  FIG. 1  where the inner dashed lines  86  closest to the slots  22  or predetermined openings  20  indicate the insert  14 . The dashed lines indicate bend lines of the attaching walls  19  of the means for mounting the back panel  82  to the flanges  16 . The back panel  82  being the insert  14  and the apertured area  88  in the preferred embodiment as seen in  FIG. 1 . 
   In the preferred embodiment, the barrier shield  10  is made of clear polycarbonate material. The width of the panel  82  is approximately 15.5 inches with a height of about 19.0 inches. Overall, the barrier shield  10  is approximately 22.25 inches by 26.0 inches, including the flanges  16  thereon. 
   It is clear that this embodiment is designed for a particular bus application and therefore may be changed appropriately. For example, the slots may very in size or number, or may be replaced with other openings such as holes or vertical slots, etc. 
     FIG. 4  is a top view of the barrier shield  10  as seen in  FIG. 3  with the shield  10  tilted backward. Similar items have the same item numbers. The numerous lines in the apertured area  88  indicate edges of the slots  22 .  FIG. 5  is a bottom view of the barrier shield  10  as seen in  FIG. 4 . As seen in  FIG. 4 , a top edge  46  of the flange  16  is shown. Dashed lines indicate bend lines in the plastic material. As seen in  FIG. 4  and  FIG. 5 , the maximum depth of the slant is approximately 2 inches over a distance of 19.0 inches, i.e., an angle of approximately 6.3 degree from the vertical direction. 
     FIG. 6  is a right side cross sectional view vertically through the barrier shield  10  of  FIG. 3  taken along line VI—VI. The sides  90  and  92  of the slots  22  are cut horizontally and perpendicular to the vertical direction of the apertured area  88  to maximize the viewing area, as shown in  FIG. 6A  which is an enlarged view of the area indicated in  FIG. 6 . One of the triangular walls  78  is clearly seen in  FIG. 6  and is on the right side of the shield  10  in  FIG. 3 . The cutting of the sides  90  and  92  of the slots  22  may be adjusted to maximize the openings as seen by an average sized seated bus driver when looking into the inside rear-view mirror. 
     FIG. 7  is an isometric perspective view from the front side of the barrier shield  10  of  FIG. 3  which clearly shows the slanted high visibility insert  14  as it is slanted away from the flange area  16  that is used to mount the barrier shield  10  to the door frame  42 . It is possible that the walls  78  and  80  may be directly connected to the door frame  42 , but this embodiment is not further shown.  FIG. 7  clearly shows the outstanding features of the unitary construction of the barrier shield  10  from a single piece of molded plastic. 
   In order to minimize manufacturing costs, the slant and the walls may be omitted and thus the back panel  82 , as a flat piece with slots, may be directly connected to the vertical door insert by itself. This clearly reduces the anti-glare and anti-reflection features of the barrier shield  10 . 
   Clearly, many modifications and variations of the present invention are possible in light of the above teachings and it is therefore understood that within the inventive concept that the invention may be practiced otherwise than specifically claimed.