Abstract:
A passenger ingress and egress system within a transit vehicle employing a movable step apparatus in combination with sliding type door system to accommodate variations in passenger ingress and egress platform facilities. Said movable step apparatus having at least three step members movable from a conventional step relation to permit ingress and egress from and onto a street platform to an aligned, coplanar relation to permit ingress and egress from and onto a commuter platform, generally located 50 inches above the Top Of Rail. A gap reduction apparatus is disposed within the movable step apparatus to minimize horizontal distance between a commuter platform and the movable step apparatus with all step members in an aligned, coplanar relation to meet federal regulations for American with Disability Act.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is related to and claims priority from U.S. Provisional Patent Application Serial No. 60/336,777 filed on Nov. 12, 2001. This application is also related to the invention disclosed in U.S. Pat. No. 3,957,284 titled “Movable steps for transit vehicle”. The teachings of U.S. Pat. No. 3,957,284 are incorporated into this document by reference thereto. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to a transit vehicle utilizing a combination of a sliding door system with a movable step apparatus disposed adjacently said sliding door system and a gap reduction apparatus disposed within said movable step apparatus for accommodating varying platform conditions of passenger ingress and egress.  
         BACKGROUND OF THE INVENTION  
         [0003]    Three different platform conditions exist in passenger ingress and egress onto and from passenger transit vehicle. The first condition relates to the passenger ingress and egress from and onto a platform which is about 8 inches above top of rail (TOR). Said platform is hereinafter referred to as a street platform. The second condition relates to the passenger ingress and egress from and onto a platform which is about 34 inches above TOR. Said platform is hereinafter referred to as a subway platform. The third condition relates to the passenger ingress and egress from and onto a platform which is about 50 inches above TOR. Said platform is hereinafter referred to as a commuter platform. Both the subway and commuter platform heights correspond to the height of the vehicular floor surface above Top of rail.  
           [0004]    Typically, a transit vehicle interfaces with only one type of the platform, however, special cases exist where said transit vehicle must be adapted to interface with more than one platform type and, more particularly, interface with a street platform and either a subway or commuter platform. In such case, the transit vehicle must incorporate means compensating for different platform height above TOR.  
           [0005]    One approach to accommodate varying platform types and, more particularly, a combination of commuter and street platforms is to incorporate a passenger ingress and egress system including a stationary stairwell disposed within floor surface in combination with a stairwell platform pivotally connected to one side of an upper horizontal plane of the stairwell and manually displaceable to lie in the horizontal plane over the stairwell for accommodating commuter platforms. This approach requires manual operation of said stairwell platform thus increasing operational costs due to necessity of having personnel to position said stairwell platform in the appropriate plane and also increases a dwell time at the station to reconfigure said stairwell platform orientation.  
           [0006]    Another approach is to incorporate a passenger ingress and egress system including movable stairwell platform in combination with a complex door construction consisting of a door lower member movably connected to an upper door member. The lower door member is for covering the stairwell opening for passenger loading from a subway or commuter platform.  
           [0007]    Yet another approach is to employ a movable step apparatus as disclosed in the U.S. Pat. No. 3,957,284. Such movable step apparatus includes a first and second steps being movable by a pneumatic drive member from a conventional relation enabling ingress and egress from and onto street platform to an aligned coplanar position creating an extension of the floor surface and, more importantly, enabling ingress and egress from and onto the subway platform. The teachings of U.S. Pat. No. 3,957,284 Movable Steps for transit vehicle are hereby incorporated into the present application by reference thereto. Said movable steps have been incorporated into a stairwell structure of a transit vehicle adjacent to a plug type door system disposed within a door portal aperture and having at least one door disposed substantially flush with the side wall of said transit vehicle in the closed position and first moving outward and then moving longitudinally, along the outer wall of said transit vehicle during opening.  
           [0008]    It has been generally accepted that for passenger safety each step within a stairwell or movable step apparatus should be approximately 10 inches wide and the vertical displacement between each step or the step and street platform should be in the range from 9 inches to 11 inches.  
           [0009]    The primary limitation of the invention disclosed in U.S. Pat. No. 3,957,284 lies in that it only accommodates the combination of street platform and subway platform. A further limitation of the invention lies in that it does not meet Federal Regulation regarding Americans with Disabilities Act (ADA) requirement that the horizontal displacement, generally referred to as the gap, between the subway or commuter platform edge and inner floor structure of the transit vehicle, with its doors open, can not exceed 3 inches. Due to the gap (or clearance) between the edge of the platform and the outer surface of the transit vehicle being approximately 3 inches and due to the door construction typically between 1 inch to 2 inches wide and required clearance with the inner surface of the door, the outer edge of the step apparatus is approximately between 4.5 inches and 5.5 inches away from the edge of the subway platform with the doors in fully open position.  
           [0010]    Subsequently, a gap reduction apparatus has been added to such movable step apparatus to meet the maximum allowable gap of 3 inches. Such apparatus having a movable member for extending into the space occupied by said at least one door upon said at least one door first moving outwardly. In such arrangement, the gap between the platform and the step apparatus is reduced prior to the door moving longitudinally and beginning to uncover the door portal opening. This arrangement allows for passenger ingress and egress while meeting the requirements set forth by ADA.  
           [0011]    It is well known in the art that pocket sliding type door systems are less complex than the plug type door system and therefore are being predominantly utilized in transit vehicles and, more particularly, are being predominantly utilized in transit vehicles interfacing with commuter and street type platforms and presently employing manually operated means for accommodating ingress and egress from and onto said commuter platform while utilizing stairwell for ingress and egress from and onto a street platform. This type of door system including at least one door movable between the inner and outer wall members of the transit vehicle for at least partially covering and uncovering a door portal opening. However, the disadvantage of the pocket sliding door system lies in that the presence of the outer wall member increases the horizontal gap to be reduced. Given the gap (or clearance) between the edge of the platform and the outer surface of the transit vehicle being approximately 3 inches, outer wall member is typically between 1.5 inches and 2 inches and door construction typically between 1 inch to 1.5 inches wide, the total horizontal gap to be overcome is approximately between 5.5 inches and 6.5 inches. Additional disadvantage in overcoming the gap lies in that the side vehicular structure curves or slops toward the underside structure of the vehicle creating an even larger distance to the stationery platform.  
           [0012]    As it can be seen from the above discussion there is a need to improve cost and efficiency of transit vehicle operation utilizing sliding pocket type door systems and accommodating street and commuter platforms while meeting various safety requirements.  
         SUMMARY OF THE INVENTION  
         [0013]    The present invention provides a passenger ingress and egress system disposed within a transit vehicle for accommodating a street platform and further accommodating a commuter platform. Such passenger ingress and egress system comprises a sliding pocket door disposed within a door portal cavity. Such passenger ingress and egress system further comprises a movable step apparatus disposed within a stairwell cavity further disposed within a floor surface.  
           [0014]    Such movable step apparatus is comprised of a frame, an inner step member, operatively mounted to said frame, said step member having a horizontally disposed upper surface at a first elevation, a middle step member operatively mounted to said frame, said second step member having a horizontally disposed upper surface at a second elevation, lower than said first elevation and an outer step member, operatively mounted to said frame, said step member having a horizontally disposed upper surface at a third elevation, lower than the said second elevation. A pneumatic drive mechanism is provided for raising said step members vertically to a fourth elevation coplanar with the floor surface while maintaining the upper surface of said raised step member in a horizontal position. Linkage means are also provided connecting said step members and being responsive to the raising of the step member for elevating the other of said step members vertically to the forth elevation while maintaining the upper surface of said step member in a horizontal position so that the upper surfaces of said step members are disposed in the same plane at the forth elevation.  
           [0015]    A gap reduction apparatus having a horizontally disposed upper surface is connected to an outer step member and driven in a substantially horizontal directions by a gap reduction drive mechanism to minimize the distance between said outer step member and commuter platform when all step members are substantially coplanar with the floor surface of the transit vehicle.  
         OBJECTS OF THE INVENTION  
         [0016]    It is therefore one of the primary objects of the present invention is to provide a means for accommodating passenger ingress and egress from and onto a street platform of 8 inches above Top Of Rail and a commuter platform of 50 inches above Top Of Rail.  
           [0017]    A further object of the present invention is to provide a means for accommodating passenger ingress and egress from and onto a street platform of 8 inches above Top Of Rail and a commuter platform of 50 inches above Top Of Rail in combination with a sliding type door system.  
           [0018]    Additional object of the present invention is to provide a means for accommodating passenger ingress and egress from and onto a street platform of 8 inches above Top Of Rail and a commuter platform of 50 inches above Top Of Rail which meets applicable regulatory requirements.  
           [0019]    Another object of this invention is to provide a means for accommodating passenger ingress and egress from and onto a street platform of 8 inches above Top Of Rail and a commuter platform of 50 inches above Top Of Rail which does not require manual intervention.  
           [0020]    Yet another object of the present invention is to provide means for accommodating passenger ingress and egress from and onto a street platform of 8 inches above Top Of Rail and a commuter platform of 50 inches above Top Of Rail employing a simple one-piece door construction.  
           [0021]    These and various other objects and advantages to the present invention will become more apparent to those persons skilled in the art from the following more detailed description, particularly, when such description is taken in conjunction with the attached drawings and the appended claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    [0022]FIG. 1 is a partial horizontal cross sectional view of a doorway of a mass transit vehicle showing doors in the closed position and gap reduction member in the partially extended position.  
         [0023]    [0023]FIG. 2 is a partial horizontal cross sectional view of a doorway of a mass transit vehicle showing doors in the open position and gap reduction member in the fully extended position.  
         [0024]    [0024]FIG. 3 is a vertical cross sectional view of the step members with a portion broken away to show the linkage means, the step members being in a substantially lowered position.  
         [0025]    [0025]FIG. 4 is a vertical cross sectional view of the step members being in a substantially raised position, with the portion broken away to show platform gap reduction member.  
         [0026]    [0026]FIG. 5 is a frontal elevation view of the drive mechanism shown through cut-away views with step members being in a substantially lowered position. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0027]    Prior to proceeding to the more detailed description of the present invention, it should be noted that for the sake of clarity identical components, having identical functions have been identified with identical reference numerals throughout the several views which have been illustrated in the drawing figures.  
         [0028]    The invention disclosed herein largely overcomes the above discussed difficulties through the use of the movable step apparatus having at least three step members to comply with the regulations regarding the vertical displacement between each step member for ingress and egress of passengers from and onto a street platform. At least one gap reduction member is employed to minimize the substantially horizontal displacement between the commuter platform and movable step apparatus having all step members in a substantially raised coplanar position. During the substantially vertical movement of all step members to the second raised position the gap reduction member first moves partially to a third position and then moves further to a forth position into the door portal aperture providing for a greatly simplified door construction comprising of one-piece member. Said two step method of the gap reduction allows first to overcome the curvature or slope of the outer side vehicular structure and substantially reduce the gap between the outer step member and the at least one door during said outer step member movement in the substantially vertical direction. The design, therefore, provides advantage of reduced manufacturing and operational costs while meeting the regulatory requirements.  
         [0029]    With reference to FIG. 1 of the present embodiment, transit vehicle  10  is illustrated having an outer wall  12  and inner wall  14  enclosing a door cavity  13 . Door portal aperture, generally designated  20 , having a first door  16  and a second door  18  is located adjacent to stairwell, generally designated  19 . First door  16  and second door  18  are movable in a substantially linear path and are shown in a substantially closed position. Movable step apparatus, generally designated  30 , comprising an inner step member, generally designated  40 , a middle step member, generally designated  50 , an outer step member, generally designated  60  is located within the stairwell cavity  19  and enclosed within first and second side frame members  32  and  34  respectively. Said first and second side frame members  32  and  34  respectively are provided to guide the vertical movement of the inner, middle and outer step members  40 ,  50  and  60  respectively between their raised and lowered positions.  
         [0030]    A gap reduction apparatus, generally designated  70 , comprising a gap reduction member, generally designated  72 , having a substantially horizontally disposed stepping surface  73  is disposed within said movable step apparatus  30 . In further reference to FIG. 1, said gap reduction member  72  is shown in partially extended third position.  
         [0031]    Furthermore, said step members  40 ,  50  and  60  are shown in a substantially raised position. Stationery commuter platform  22  is located adjacent to door portal aperture  20  and separated by distance  21  from the outer wall surface  12 .  
         [0032]    In reference to FIG. 2, the first door  16  and second door  18   r  are shown in their substantially open position enclosed within the door cavity  13 . Said gap reduction member  72  is shown in its substantially extended forth position establishing a distance  23  from the commuter platform  22  being approximately 50 inches above the top of rail surface  26 .  
         [0033]    Said movable step apparatus  30  is further shown in its first position being a substantially lowered conventional step configuration in FIG. 3. In this configuration the vertical displacement between inner, middle and outer step members  40 ,  50  and  60  respectively is approximately 10.5 inches. An upper substantially horizontal stepping surface  42  of the inner step member  40  is positioned at a first elevation with the substantially horizontal stepping surface  52  of the middle step member  50  is positioned at a second lower elevation and with the substantially horizontal stepping surface  62  of the outer step member  60  at a third lower elevation. In this position, a passenger may ingress the vehicle from a street platform  24 , being approximately 8 inches above top of rail surface  26 , stepping onto the outer step member  40  and further proceeding to the floor surface  28  of the transit vehicle  10 . The gap reduction member  72  is shown disposed in a substantially horizontal position under the stepping surface  62 .  
         [0034]    In this configuration a substantially vertical surface  44  of the inner step member  40  extends vertically past the middle member  50 . Similarly, a substantially vertical surface  54  of the middle step member  50  extends vertically past the outer member  60 .  
         [0035]    A drive assembly, generally designated  80 , enables to raise stepping surfaces  62 ,  52  and  42  to a second position being a fourth elevation substantially aligned in coplanar relation with the floor surface  28  of the transit vehicle  10 , as illustrated in FIG. 4. Gap reduction member  72  is disposed in the substantially horizontal position inside the portal aperture  20  and creating a reduced distance  23  with the commuter platform  22 . In this position passengers may egress onto the commuter platform  22  located substantially coplanar with the floor surface  28 .  
         [0036]    At least one first linkages, generally designated  100 , connects the inner step member  40  and middle step member  50  and is responsive to the raising of said inner step member  40  to said second position coplanar with the floor surface  28  to raise the middle step member  50  to said second position while maintaining the upper surfaces  42  and  52  of the step members  40  and  50  respectively in a substantially horizontal position. In the preferred embodiment said at least one first linkage  100  is a plurality of first linkage  100  disposed at each end of the inner step member  40  and middle step member  50 .  
         [0037]    The first linkage  100  comprises a first linkage arm  110  having first end  112  and second  114 . The first end  112  of linkage arm  110  is pivotally connected to the middle step member  50  at pivot portion  116 . Pivot means  118  disposed within said linkage arm  110  is provided for mounting the second end  114  of linkage arm  110  to the frame of the vehicle  10  on the opposite side of the inner step member  40 . The pivot means  118  permits pivotal movement of the first linkage arm  110  about a pivot point  116  while also providing for reciprocal swinging movement of the pivot point  116  toward and away from the step members  40 ,  50  and  60 . The first linkage  100  further comprises a second linkage arm  120  pivotally connected to the first linkage arm  110  intermediate its ends  112  and  114  and pivotally connected to the inner step member  40 .  
         [0038]    At least one second linkage, generally designated  130 , connects the outer step member  60  to the middle step member  50  and is responsive to the raising of the middle step  50  to raise the outer step member  60  to the fourth elevation coplanar with the floor surface  28 . The second linkage  130  comprises a linkage arm  132  pivotably connected to the outer step member  60  at the first end  134  and pivotably connected to the middle step member  50  at the pivot  138  disposed intermediate a first end  134  and a second end  136  having a sliding member  140 . In the preferred embodiment sliding member  140  is a roller. In the preferred embodiment said at least one second linkage  130  is a plurality of second linkage  130  disposed at each end of the middle step member  50  and outer step member  60 .  
         [0039]    As best shown in FIG. 5, the step drive mechanism, generally designated  80 , for raising and lowering the step members  40 ,  50  and  60  comprises a support assembly, generally designated  84 , including a frame member  86  attached to stairwell structure  19 , a first lift arm  88  and a second lift arm  90  pivotably connected to said frame member  86  and joined by a brace member  92 . A third lift arm  89  is pivotably connected to frame member  86  and substantially connected to first lift arm  88 . At least one prime mover  82  is pivotally attached to frame member  86  at one end and pivotally connected to third lift arm  89  at a distal end. In the preferred embodiment said prime mover  82  is a double acting pneumatic cylinder. Alternatively, said prime mover can be a rodless pneumatic cylinder, a hydraulic cylinder or an electric linear drive mechanism.  
         [0040]    As may be seen in FIGS. 3 and 4, in sequence, the step members  40 ,  50  and  60  are, in FIG. 3, in the first position being a conventional step relation to provide ingress onto the floor surface  28  of the vehicle  10  through the stairwell  19  from a street platform  24 . In order for the step apparatus  30  to accommodate ingress and egress of passengers from and onto a commuter platform  22 , the step members  40 ,  50  and  60  respectively are raised to the second position substantially coplanar with the floor surface  28 , as best shown in FIG. 4.  
         [0041]    To accomplish this position shift, the pneumatic system is charged causing third lift arm  89  to rotate in counterclockwise direction  130  and causing said first lift arm  88  and said second lift arm  90  to rotate in the same counter-clock direction  130 . The rotation of said lift arms raises step member  40  to the fourth elevation substantially coplanar with the floor surface  28 .  
         [0042]    The raising of the inner step member  40  in the manner just described to the fourth elevation causes the plurality of first linkage arm  100  to rotate about the pivot  116  raising the middle step member  50  to the fourth elevation substantially coplanar with the floor surface  28 . Furthermore, substantially vertical movement of the middle step  50  rotates the link arm  130  about the pivot  142  causing the outer step  60  to rise to the fourth elevation.  
         [0043]    The method of reducing the gap between the outer step member  60  and the commuter platform  22  consists of two steps. In the first step, during the vertical movement of the outer step member  60 , the gap reduction member  72  disposed underneath the stepping surface  62  is partially driven in the direction  11  by gap reduction drive mechanism, generally designated  74 , with said first door  16  and said second door  18  being in a substantially closed position within said portal cavity  20 . It can be easily seen that such direction  11  is substantially perpendicular to the movement path of said first door  16  and said second door  18 . In the second step, as said first door  16  and said second door  18  reach their respective full open positions said gap reduction drive mechanism  74  further drives gap reduction member  72  in the direction  11  resulting in the substantially reduced distance  23  to the edge of the commuter platform  22  meeting the ADA requirements. The gap reduction drive mechanism  74  can employ a hydraulic or electric prime mover, but preferably employs at least one pneumatic prime mover  76  (not shown).  
         [0044]    As has been described herein before, the movable step apparatus  30  and gap reduction apparatus  72  cooperate with a pair of bi-parting first door  16  and second door  18   r  for at least partially covering and uncovering door portal aperture  20 . Those skilled in the art can easily recognized that operation of said movable step apparatus  30  and said gap reduction apparatus  70  will be identical in the case of a single door  16  or  18  for covering and uncovering said door portal aperture  20 .  
         [0045]    Although a presently preferred and various alternative embodiments of the present invention have been described in considerable detail above with particular reference to the drawing FIGURES, it should be understood that various additional modifications and/or adaptations of the present invention can be made and/or envisioned by those persons skilled in the relevant art without departing from either the spirit of the instant invention or the scope of the appended claims.