Passenger entrance ramp for mass transit vehicle

Information

  • Patent Grant
  • 6343908
  • Patent Number
    6,343,908
  • Date Filed
    Friday, April 21, 2000
    24 years ago
  • Date Issued
    Tuesday, February 5, 2002
    23 years ago
Abstract
A public transit vehicle has a passenger entrance ramp at a door way including a support frame for mounting on the vehicle at the doorway carrying a primary ramp panel, a secondary ramp panel and a fixed platform panel. The primary panel is pivotal through 180 degrees between a retracted position inverted within the vehicle and covering the secondary panel and the fixed platform panel and a deployed position in which the primary ramp panel is inclined from an inner edge downwardly and outwardly from the vehicle to an outer edge at the ground. The primary panel is pivoted at its inner edge on an outer edge of the secondary ramp panel pivotal which is in turn pivotal about an inner horizontal axis at its inner edge. The primary and secondary ramp panels are thus arranged such that, in the retracted position, the outer edge of the secondary panel is in the raised position so that both the primary and secondary ramp panels are substantially horizontal and, in the deployed position, the outer edge is moved to the lowered position so that the primary and secondary ramp panels form a common ramp surface inclined outwardly and downwardly from the inner edge of the secondary ramp panel to the outer edge of the primary ramp panel.
Description




This invention relates to passenger entrance ramp of a mass transit vehicle.




BACKGROUND OF THE INVENTION




It is a requirement of many passenger transit vehicles that there be provided a ramp system at a doorway of the vehicle so that passengers in a wheelchair can conveniently move from the ground surface adjacent to the vehicle onto the floor of the vehicle for transportation in the vehicle.




One example of a ramp arrangement which is particularly convenient for low floor transit vehicles is shown in U.S. Pat. 5,391,041, issued Feb. 21, 1995 to the present assignee.




This arrangement of ramp is suitable for low floor vehicles because it is located at floor level without any necessity for storage under the floor, bearing in mind that the low floor configuration reduces the height of the floor to a position where there is little space under the floor for storage of ramp elements. However some telescoping ramps have been provided and stored under the floor of a low floor chassis. However these are limited in the variation in incline which can be provided and are subject to failure as a consequence of continuous exposure to the elements and damage from curbs and other obstacles.




The ramp construction of the above patent therefore provides a ramp panel which is pivoted at its inner edge to the structure and rotates through an angle slightly greater than 180° from a retracted position lying flat on the floor inside the vehicle to a deployed position where it extends outwardly from the pivot axis and slightly downwardly into contact with the ground.




The length of the panel in a direction across the width of the vehicle is limited by the fact that the door is generally located at the driver compartment so that the length of the panel is slightly greater than one half the width of the vehicle. In a situation where the ramp extends from the floor height downwardly and outwardly onto a raised curb, the angle of the ramp is generally acceptable and is not excessive thus interfering with the movement of the wheelchair up a ramp and into the vehicle. However in a situation where there is no curb so that the ramp must accommodate the full height from the floor to the ground, the angle of the ramp may exceed a desirable angle. Some vehicles of this type have a kneeling action by which the front suspension of the vehicle is slightly lowered by a height of the order of two to three inches thus again reducing the angle of the ramp. However this is generally insufficient to provide a ramp of the required angle.




SUMMARY OF THE INVENTION




It is one object of the present invention, therefore, to provide an improved passenger entrance ramp for a mass transit vehicle which allows a reduced angle of the ramp without increasing the length of a primary pivoting element of the ramp and therefore its intrusion into the area of the driver's compartment.




According to a first aspect of the invention there is provided a passenger entrance ramp assembly for a public transit vehicle, the vehicle having a door way through which passengers pass for entering or departing the vehicle with a bottom edge of the doorway at floor level of the vehicle, the ramp assembly comprising:




a support structure for mounting on the vehicle at the doorway;




a primary ramp panel arranged at the doorway for movement between retracted position within the vehicle and a deployed position in which the primary ramp panel is inclined from an inner edge downwardly and outwardly from the vehicle to an outer edge at the ground;




a secondary ramp panel having an outer edge at the bottom edge of the doorway and an inner edge generally parallel to the outer edge and spaced inwardly therefrom;




the primary ramp panel being mounted for pivotal movement relative to the secondary ramp panel about an outer horizontal axis at the outer edge of the secondary ramp panel through an angle of the order of 180 degrees between the deployed position and the retracted position such that in the retracted position the primary ramp panel is inverted on top of the secondary ramp panel;




the secondary ramp panel being mounted on the support structure for pivotal movement about an inner horizontal axis at the inner edge such that the outer edge and the outer horizontal axis move upwardly and downwardly between a raised horizontal position and a lowered position;




the primary and secondary ramp panels being arranged such that, in the retracted position, the outer edge is in the raised position so that both the primary and secondary ramp panels are substantially horizontal and, in the deployed position, the outer edge is moved to the lowered position so that the primary and secondary ramp panels form a common ramp surface inclined outwardly and downwardly from the inner edge of the secondary ramp panel to the outer edge of the primary ramp panel.




Preferably the primary ramp panel is arranged to float at the deployed position.




Preferably the primary and the secondary ramp panels are located at the same ramp angle when deployed.




Preferably there is provided a fixed horizontal platform panel arranged at the inner edge of the secondary ramp panel and extending therefrom to an innermost edge generally parallel to the inner edge of the secondary ramp panel.




Preferably the primary ramp panel in the retracted position overlies and covers the secondary ramp panel and at least part of the platform panel.




Preferably the platform panel, the secondary ramp panel and the primary ramp panel are equal in width.




Preferably the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator and the secondary panel is moved between the retracted position and the deployed position by a secondary panel power actuator and wherein there is provided a control for controlling actuation of the secondary panel power actuator separately from the primary panel power actuator such that the secondary ramp panel can be actuated to move to the deployed position only if required and only after the primary ramp panel has been deployed and rotated through an angle of the order of 170 degrees relative to the secondary ramp.




Preferably the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator comprising a hydraulic cylinder, a first pulley connected to the cylinder, a second pulley connected to a pivot shaft of the primary ramp panel and a flexible continuous member engaged around the first and second pulleys forming communicating drive therebetween.




Preferably the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator and the secondary panel is moved between the retracted position and the deployed position by a secondary panel power actuator and wherein the primary and secondary panel power actuators include hydraulic actuators and are operated by a common hydraulic circuit.




Preferably the primary ramp panel is movable manually from the deployed position to the retracted position.




Preferably there is provided an abutment member for contacting the primary ramp panel when moved to the retracted position for lifting the secondary ramp panel into the retracted position.




Preferably the primary ramp panel is mounted at the outer edge of the secondary ramp panel by a hinge for pivotal movement about the hinge.




Preferably the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator comprising a rotary hydraulic actuator, a pivot shaft and a right angle gear box communicating drive from the actuator to the pivot shaft.




Preferably the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator and wherein the primary panel power actuator is mounted on the support for pivotal movement about the inner pivot axis.




Preferably movement of the secondary ramp panel is actuated by a pair of crank members each arranged at a respective side of the second ramp panel and each having a support roller engaging a respective support track on the support member for support thereby, the crank members being connected to a transverse drive shaft connected across the second ramp panel and driven by a hydraulic actuator such that rotation of the shaft causes the cranks to raise and lower the second ramp panel.




Preferably and the rollers are free to lift from the respective support track to allow manual movement of the second ramp panel from the deployed position to the retracted position.




Preferably the shaft is rotated by a drive cylinder acting on a crank connected to the shaft with a dog leg drive link between the cylinder and the crank.











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 showing primarily a passenger entrance ramp according to the present invention in a retracted position of the ramp with the drive components omitted for convenience of illustration.





FIG. 2

is a side elevational view from the opposite side relative to that of

FIG. 1

showing the ramp only in a partly deployed position in which the primary ramp panel is moved through 180 degrees to its outwardly extending position.





FIG. 3

is a similar side elevational view to that of

FIG. 2

showing the ramp in its fully deployed position.





FIG. 4

is an isometric view from the top and one side showing the ramp only in the retracted position of FIG.


1


and showing particularly the drive actuator of the primary ramp panel.





FIG. 5

is an isometric view similar to that of

FIG. 4

showing the ramp only in the fully deployed position of FIG.


3


.





FIG. 6

is an isometric view from the bottom and the opposite side of the ramp only in the partly deployed position of FIG.


2


.





FIG. 7

is a side elevational view showing the secondary ramp panel only in the partly deployed position of FIG.


2


.





FIG. 8

is a side elevational view similar to that of

FIG. 7

showing the secondary ramp panel only in the fully deployed position of FIG.


3


.





FIG. 9

is an isometric view of an alternative drive arrangement for actuating movement of the primary ramp panel.





FIG. 10

is a schematic illustration of the hydraulic circuit for operating the drive actuators of the primary and secondary ramp panels.











DETAILED DESCRIPTION




A transit vehicle


10


is shown in cross section in FIG.


1


. This includes side walls


11


, a roof


12


and a floor


13


mounted on a suitable frame structure


14


. The details of the vehicle structure are well known to one skilled in the art and can vary in accordance with design requirements.




The vehicle includes rows of seats


14


shown in phantom together with a drivers compartment


15


on a side of the vehicle opposite to a doorway


16


through which passengers can enter and depart from the vehicle. In front of the rows of seats is provided an entry platform area generally indicated at


17


onto which the passengers can enter by stepping over an entry threshold


18


before turning and entering an alleyway


19


between two rows of seats.




The floor


13


is arranged at a low height, where able bodied passengers can step from ground level


20


directly onto the platform surface without the need for steps between the two. However it is essential also in transit vehicles of this type to provide a ramp by which a wheelchair occupant can also enter the vehicle. The ramp is generally deployed only when an potential passenger utilizing a mobility aid such as a wheel chair presents him or herself for entry, and therefore at most stops the passengers are expected to enter the vehicle without the assistance of the ramp.




The use of the low floor structure provides very little area underneath the floor for the mounting of the ramp structure. Therefore the ramp structure is provided at the floor level of the floor


13


and forms the entry platform onto which the able bodied passengers step while at the same time being movable into a deployed position in which the sections of the platform move outwardly to form a ramp allowing the wheelchair occupant to enter up the ramp onto the platform area.




Turning now to

FIG. 4

, showing an isometric view of the retracted ramp assembly which provides the platform for the able bodied passengers and also can be deployed to the position shown in

FIG. 5

for use as a ramp.




The ramp structure therefore generally indicated at


22


includes a surrounding support


23


, a fixed platform panel


24


, a primary ramp panel


25


and a secondary ramp panel


26


.




In general, the fixed platform panel


24


has an innermost edge


27


and an outer edge


28


. The secondary ramp panel has an inner edge


29


pivotal about a hinge structure at the inner edge


29


. The secondary ramp panel has an outer edge


30


and the primary ramp panel is pivotal about a hinge structure at an inner edge


31


of the primary ramp panel which coincides with the outer edge of the secondary ramp panel. The primary ramp panel has an outermost edge


32


arranged to rest on the ground as an entry edge over which the wheelchair rolls in the deployed ramp position of the ramp structure.




Thus in general the ramp structure can be moved to the retracted position shown in

FIG. 4

in which the primary ramp panel


25


is inverted and covers both the secondary ramp panel and the fixed platform panel. All the panels are horizontal in this position and the outermost edge


32


is moved to a position substantially overlying the innermost edge


27


. These three panels have a common width between two parallel side rails


34


and


35


of the support


23


. Thus in the position shown in

FIGS. 1 and 4

, the underside of the primary ramp panel acts as the platform onto which the able bodied passenger can enter, stand and leave.




In general in a first deployment movement, the primary ramp panel


25


rotates about the hinge at the inner edge


30


through an angle of the order of 180 degrees so that it moves from the inverted position on top of the panels


24


and


26


to the position shown in

FIG. 2

where the primary ramp panel projects outwardly to one side of the vehicle that is beyond the threshold at the outer edge


30


of the secondary ramp panel. In this position shown in

FIG. 2

, the primary ramp panel


25


can move downwardly so that the outer edge


32


moves into engagement with a curb


36


to act as a ramp over which the wheelchair can pass up the inclined ramp surface onto the horizontal secondary ramp panel


26


. The primary ramp panel


25


is free to float around the position shown in

FIG. 2

so it can take up the required height on the curb


36


simply by floating downwardly to the required position until it stops butting the curb


36


. The downward floating action prevents the application of downward force by the ramp panel onto a toe or an other element which can be damaged.




In the event that there is no curb and it is necessary for the bottom edge


32


of the primary ramp panel to move downwardly beyond the height of the curb to the ground level the secondary ramp panel


26


can also move downwardly from the raised horizontal position shown in

FIG. 2

to the lowered position showed in FIG.


3


. Thus its inner edge


29


remains in the horizontal plane of the platform panel while its outer edge


30


moves downwardly to the lowered position as shown in FIG.


3


. The primary and secondary ramp panels in most deployment situations form a single ramp extending from the outermost edge


32


to the inner edge


29


. The length of the ramp so formed is thus significantly longer than the length of the primary ramp panel itself thus reducing the angle necessary to accommodate the height between the height of the floor and the ground surface.




It is undesirable that the primary and secondary ramps when both deployed take up a position in which the angle between the ramps is different from 180 degrees. The inclined of the primary and secondary ramps should therefore be the same when both ramps are deployed. The operator is therefore instructed when actuating the secondary ramp at the end of movement of the primary ramp to ensure that both ramps are in a flat plane before allowing boarding.




While the angle of the primary ramp alone necessary to bridge the whole of the difference in height between the floor and the ground surface would be in practice too steep for reasonably and safely accommodating wheelchair access, the angle of the combined ramp is reduced and therefore is within the acceptable range for the wheelchair.




In general, therefore, the operator can operate initially the primary ramp panel to deploy to outwardly extended position and can then choose to operate the secondary ramp panel if necessary so as to provide the required angle. Normally the operator will determine in advance whether there is a curb to be engaged by bottom edges


32


and will choose in advance whether to deploy or not to deploy the secondary ramp panel.




The geometry of the ramp structure is such that it extends in the retracted position shown in

FIG. 4

from the threshold


18


to a position spaced from the edge of the driver's compartment


15


. The edge


17


A of the ramp structure is spaced from the edge


15


A of the driver's compartment leaving a fixed platform portion therebetween which defines a portion of the alleyway.




The ramps are fully deployed, as described hereinafter, there is a horizontal space between the fixed platform and the elevated driver's platform. This space is occupied at its forward end by the fare collection box and associated stanchion. The combined elements formed by the fixed platform


24


is described hereinafter and the area


17


B between the edges


17


A and


15


A create a substantially level horizontal platform which provides a secure resting area for the wheelchair once it has negotiated the ramp. Upon this point the wheelchair can be turned without danger of rolling back down the ramp or tilting over sideways during the turning manoeuvre.




The platform panel forms approximately one half of the length of the primary ramp panel so it is substantially equal to the length of the secondary ramp panel. This provides a length of the platform panel


24


and the fixed floor panel from the driver's compartment


15


which is approximately equal to the width of the alleyway allowing the wheelchair to pass over the top of the ramp at the inner edge


29


and to turn on the platform panel into the alleyway to enter the vehicle. In addition this provides a length of a secondary ramp panel which is sufficient to supplement the length of the primary ramp panel to form a composite ramp of sufficient length to provide the required slope while accommodating the full height between the floor and the ground. In this regard, some vehicles of this type may have a kneeling action where the driver can lower the suspension by a distance of the order of two inches so as to further reduce the height between the floor and the ground surface.




The primary ramp panel


25


is formed by a flat sheet of a suitable material which is stiffened by a pair of upstanding flanges


38


each along a respective side edge of a panel. In the deployed position the flanges


38


stand upwardly and thus form side guides which prevent the wheels of the wheelchair from slipping over one side edge if misdirected. In the retracted position, the flanges


38


engage just inside the side rails


34


and


35


of the support frame and into a slot defined between the platform panel


24


and the secondary ramp panel


26


and the side rails


34


and


35


. Thus in the retracted position shown in

FIG. 4

, the sheet defining the ramp panel lies flat on the top surface of the sheets forming the panel


24


and


26


with the flanges projecting downwardly into the slots.




The hinge between the secondary and primary ramp panels at the edge is


30


and


31


is formed by a continuous hinge arrangement generally indicated at


40


and connecting the sheets forming tho s e ramp panels. Similarly a continuous hinge structure


41


is provided at the inner edge


29


of the secondary ramp panel.




The pivotal movement of the primary ramp panel is driven by a shaft


43


connected to the primary ramp panel at the hinge


40


so the shaft


43


has an axis coincident with the axis of the hinge. The shaft is driven by an actuator generally indicated at


44


which is mounted alongside the rail


35


and extends from the hinge


40


to a mounting pivot pin


45


which is located at a position directly coincident with the axis of the hinge


41


. The actuator comprises of a pair of side rails


46


which extend between the pin


45


and the shaft


43


and thus hold the structure rigid while it is free to pivot about the pin


45


and therefore to follow movement of the secondary ramp panel


26


.




In the embodiments shown in

FIGS. 4 and 5

, the actuator comprises a linear hydraulic cylinder


47


which drives a crank


48


connected to a pulley


49


. The pulley


49


co-operates with a pulley


50


connected to the shaft


43


. A suitable drive member


51


interconnects the pulleys so the rotation of the pulley


49


acts to rotate the pulley


50


and thus to drive the shaft. The pulley


49


is of significantly larger diameter then the pulley


50


so that a relatively small angle of movement of the pulley


49


rotates the pulley


50


though approximately 180 degrees. The continuous drive member


51


is in the embodiment shown a tooth belt which could also be a chain or any other positive drive arrangement which ensures that a predetermined distance of movement of the cylinder


47


generates a predetermined angle of movement of the shaft


43


and therefore the primary ramp panel.




The mounting of the primary ramp actuation device


44


on a bracket which allows the cylinder, belt and drive mechanism to move downwardly with the motion of the secondary ramp allows the actuation of the secondary ramp without the necessity for it to be decoupled from the primary ramp actuator.




In

FIG. 9

is shown an alternative arrangement of the actuator indicated at


44


A where the drive mechanism is mounted on the end of an arm


46


A pivotal on the pin


45


as previously described. The device operates to drive the shaft


43


as previously described but in this arrangement there is provided a rotary vane actuator


47


A in replacement for the linear cylinder


47


, the output of which drives a right angle gear box


49


A in which the shaft


43


is mounted. The elements are therefore mounted on the end of the arm


46


A in a manner which allows the components to be mounted inboard of the side wall of the vehicle in front of the doorway and adjacent the threshold. The rotary vane cylinder thus stands in a substantially vertical direction for rotation about a vertical axis and this arrangement provides the necessary compactness of design in view of the limited space available both in the underfloor area and in the area in front of the door opening.




Turning now to

FIGS. 6

,


7


and


8


, the secondary ramp panel and arrangement for driving the movement of the secondary ramp panel is shown. The secondary ramp includes a top sheet and an underlying frame formed by longitudinal and transverse ribs. The drive comprises a linear actuating cylinder


60


pivotally mounted on a frame member


61


of the secondary ramp panel and extending along the length of the secondary ramp panel parallel to and underneath the secondary ramp panel. A transverse drive shaft


62


carries a crank


63


which is driven by the cylinder so as to rotate the shaft


62


through an angle of the order of 120°. The crank


63


carries a pivot pin


64


which connects to a dog leg link


65


originally connected to the end of the piston of the cylinder


60


. Pivotal movement of the dog leg link


65


caused by the eccentricity of the crank


63


is taken up by the pivotal mounting of the cylinder


60


on the frame member


61


. The shape of the dog leg link allows it to engage around the shaft in the outer extreme of its movement as shown in FIG.


8


. As shown in

FIG. 6

the cylinder and the link are mounted centrally of the shaft and the shaft extends outwardly to the sides of the secondary ramp panel and is supportive for rotation about its axis in suitable bearings


66


carried in longitudinal frame members


67


. At each end of the shaft


62


is provided a crank


68


which carries on its end remote from the shaft a roller


69


. The roller


69


engages onto a track


70


which is attached to the respective side rail


34


,


35


. The track is substantially horizontal and provides a support for the roller so that the height of the shaft


62


relative to the track


70


is governed by the angle of the crank


68


around the axis of the shaft


62


.




As shown in

FIG. 7

, the shaft stands vertically upwardly above the roller


69


so that it is raised to its maximum height relative to the fixed track


70


. In

FIG. 8

, the shaft


62


is moved downwardly relative to the track


70


as the crank


68


is inclined downwardly from the track. At the same time the roller


69


moves along the track. The track has raised ends


70


A and


70


B to confine the roller on the track. An adjustment screw


71


provides an abutment limiting the movement of the roller in the direction toward the cylinder thus preventing the crank


63


and the link


65


from going over center.




As the shaft


62


is rigidly attached to the frame of the secondary ramp panel, raising and lowering of the shaft


62


therefore raises and lowers the outer end of the secondary ramp panel from the raised position shown in

FIG. 7

to the lowered or deployed position shown in FIG.


8


.




In the event of a failure of the actuation system for the primary and secondary ramps, the primary ramp can be manually moved from its deployed position to its retracted position. This movement causes the edges of the flanges


38


to engage onto an abutment


75


carried on the side rail


34


and


35


thus acting to lift the secondary ramp portion from its deployed position to its retracted position so that the whole of the platform defined by the inverted primary ramp portion sits on the abutment


75


at the outer end of the support structure. Thus, in the event of failure, the platform structure within the bus can be restored to its retracted position for normal operation of the vehicle. The secondary ramp panel is lifted from the position shown in

FIG. 8

while the cylinder and the cranks remain in the position of

FIG. 8

simply by lifting the rollers


69


away from the track


70


to a position immediately underlying the side rails


34


and


35


.




Turning now to

FIG. 10

there is shown schematically a hydraulic circuit for actuating the cylinders


47


and


60


. The hydraulic circuit includes a pump


76


and a return sump


77


with a filter


77


A. A pressure relief valve


77


B allows pump pressure to be dumped in the event of an obstacle causing an overpressure situation in the feed line. A manually operable control lever


78


is movable between three positions indicated at “stow”, “float”, “deploy”. The control lever


78


actuates a valve control system


80


which supplies fluid to the deploy and stow inlets of the cylinder


47


and


60


. A position switch


81


detects the movement of the primary ramp panel so that the switch is actuated prior to the primary ramp panel reaching its extreme positions both retracted and deployed. The position switch


81


is provided as a pair of micro switches on a mounted panel


82


carried on the actuator


44


.




The manifold


80


includes three solenoid actuated valves


80


A,


80


B and


80


C. Each of these can be actuated for connection to the positive pressure line P from the pump or to the drain line D to the sump.




The control system


80


further includes a pilot actuated bypass valve


80


D which is actuated by pressure on the lines on the valve


80


A so as to effect bypass from the line


1


to line


4


. It will be noted that the lines


1


,


2


,


3


and


4


are connected to the secondary cylinder deploy, secondary cylinder stow, primary cylinder deploy and primary cylinder stow respectively.




The position switch


81


also engages an interlock system that prevents movement of the vehicle or closure of the door while the ramp is deployed.




The position switch


81


further acts to prevent deployment of the secondary ramp until the primary ramp assumes an angle greater than 160 degrees with respect to the secondary ramp. This means that deployment, float and stow control can be managed through the single control switch


78


described above. The default position of the control switch is a floating condition. The primary ramp floats down as described until it contracts the ground. Further actuation of the switch in the deploy position actuates the secondary ramp. The position sensing switch also acts to lock the two ramps together in the further deployment phase so that at no time can the ramps assume different inclines in respect to each other.




The build up of hydraulic pressure is limited by the relief valve on the pump. This has a preset upper limit so that if the ramp encounters resistance during deployment and pressure in the system builds to a level which is greater than the pressure required to actuate the ramp, the relief valve opens relieving pressure and reversing the motion of the ramp. A circuit is also provided whereby the operator can halt the motion of the ramp during deployment and hold it in position until such time as obstacles are cleared out of the path of deployment. This arrangement is an optional feature which is not shown in the arrangement as illustrated since it requires a further position of the control device


78


.




In operation, the valve control is normally maintained in the float position and in this position fluid is free to flow in each of the cylinders


47


and


60


between the deploy and stow outlets through the valve control


80


so that the aforementioned manual operation can be effected without resistance from the cylinder and so that the primary ramp panel is free to float downwardly under gravity when it reaches positions adjacent to the retracted and deployed position to prevent movement in these areas under power which could cause trapping and damage of an intervening element. In addition the float position allows the primary ramp panel to move to the required position at whatever angle is required to accommodate the exact height of the curb.




In the stow position of the control lever, the valve control system operates to supply pump pressure to the stow inlets of the cylinders


47


and


60


simultaneously so as to drive the primary and secondary ramp panels into the retracted position. As the primary ramp panel moves to the retracted position, the position detector detects the movement and releases the supply of fluid to the cylinder


47


allowing the primary ramp panel to float downwardly into the fully retracted position without power.




Further details of the hydraulic circuit will be known to one skilled in the art and therefore detailed circuit components do not need to be described herein. Further information is available from the aforementioned patent of the present assignees and reference to this document can be made if required for such further details.




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.



Claims
  • 1. A passenger entrance ramp assembly for a public transit vehicle, the vehicle having a doorway through which passengers pass for entering or departing the vehicle with a bottom edge of the doorway at floor level of the vehicle, the ramp assembly comprising:a support structure for mounting on the vehicle at the doorway; a primary ramp panel arranged at the doorway for movement between a retracted position within the vehicle and a deployed position in which the primary ramp panel is inclined from an inner edge of the primary ramp panel downwardly and outwardly from the vehicle to an outer edge of the primary ramp panel at the ground; a secondary ramp panel having an outer edge of the secondary ramp panel at the bottom edge of the doorway and an inner edge of the secondary ramp panel generally parallel to the outer edge of the secondary ramp panel and spaced inwardly therefrom; the primary ramp panel being mounted for pivotal movement relative to the secondary ramp panel about an outer horizontal axis at the outer edge of the secondary ramp panel through an angle of the order of 180 degrees relative to the secondary ramp panel while moving between the deployed position and the retracted position such that in the retracted position the primary ramp panel is inverted on top of the secondary ramp panel; the secondary ramp panel being mounted on the support structure for pivotal movement about an inner horizontal axis at the inner edge of the secondary ramp panel such that the outer edge of the secondary ramp panel and the outer horizontal axis move upwardly and downwardly between a raised horizontal position and a lowered position; the primary and secondary ramp panels being arranged such that, in the retracted position, the outer edge of the secondary ramp panel is in the raised position so that both the primary and secondary ramp panels are substantially horizontal and, in the deployed position, the outer edge of the secondary ramp panel is moved to the lowered position so that the primary and secondary ramp panels form a common ramp surface inclined outwardly and downwardly from the inner edge of the secondary ramp panel to the outer edge of the primary ramp panel.
  • 2. The entrance ramp according to claim 1 wherein, if the secondary ramp panel is deployed, the primary and secondary ramp panels are maintained in a common plane.
  • 3. The entrance ramp according to claim 1 wherein there is provided a fixed horizontal platform panel arranged at the inner edge of the secondary ramp panel and extending therefrom to an innermost edge of the platform panel generally parallel to the inner edge of the secondary ramp panel.
  • 4. The entrance ramp according to claim 3 wherein the primary ramp panel in the retracted position overlies and covers the secondary ramp panel and at least part of the platform panel.
  • 5. The entrance ramp according to claim 3 wherein the innermost edge of the platform panel is arranged at a position spaced from an edge of a driver's compartment and the primary ramp panel covers substantially all of the platform panel.
  • 6. The entrance ramp according to claim 3 wherein the platform panel from the innermost edge of the platform panel to the inner edge of the secondary panel is substantially equal in length to the length of the secondary ramp panel from the inner edge of the secondary ramp panel to the bottom edge of the doorway.
  • 7. The entrance ramp according to claim 3 wherein the platform panel, the secondary ramp panel and the primary ramp panel are equal in width.
  • 8. The entrance ramp according to claim 1 wherein the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator and the secondary panel is moved between the retracted position and the deployed position by a secondary panel power actuator and wherein there is provided a control for controlling actuation of the secondary panel power actuator separately from the primary panel power actuator.
  • 9. The entrance ramp according to claim 1 wherein the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator comprising a hydraulic cylinder, a first pulley connected to the cylinder, a second pulley connected to a pivot shaft of the primary ramp panel and a flexible continuous member engaged around the first and second pulleys for communicating drive therebetween.
  • 10. The entrance ramp according to claim 1 wherein the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator and the secondary panel is moved between the retracted position and the deployed position by a secondary panel power actuator and wherein the primary and secondary panel power actuators include hydraulic actuators and are operated by a common hydraulic circuit.
  • 11. The entrance ramp according to claim 8 wherein the primary ramp panel is movable manually from the deployed position to the retracted position.
  • 12. The entrance ramp according to claim 11 wherein there is provided an abutment member for contacting the primary ramp panel when moved to the retracted position for lifting the secondary ramp panel into the retracted position.
  • 13. The entrance ramp according to claim 1 wherein the primary ramp panel is mounted at the outer edge of the secondary ramp panel by a hinge for pivotal movement about the hinge.
  • 14. The entrance ramp according to claim 1 wherein the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator comprising a rotary hydraulic actuator, a pivot shaft and a right angle gear box communicating drive from the actuator to the pivot shaft.
  • 15. The entrance ramp according to claim 1 wherein the primary ramp panel is moved between the retracted position and the deployed position by a primary panel power actuator and wherein the primary panel power actuator is mounted on the support for pivotal movement about the inner horizontal axis.
  • 16. The entrance ramp according to claim 1 wherein movement of the secondary ramp panel is actuated by a pair of crank members each arranged at a respective side of the secondary ramp panel and each having a support roller engaging a respective support track on the support structure for support thereby, the crank members being connected to a transverse drive shaft connected across the secondary ramp panel and driven by a hydraulic actuator such that rotation of the shaft causes the cranks to raise and lower the secondary ramp panel.
  • 17. The entrance ramp according to claim 16 wherein the rollers are free to lift from the respective support track to allow manual movement of the secondary ramp panel from the deployed position to the retracted position.
  • 18. The entrance ramp according to claim 16 wherein the shaft is rotated by a drive cylinder acting on a crank connected to the shaft with a dog leg drive link between the cylinder and the crank.
US Referenced Citations (5)
Number Name Date Kind
4381899 Merkle May 1983 A
4792274 Cockram Dec 1988 A
5391041 Stanbury et al. Feb 1995 A
5871329 Tidrick et al. Feb 1999 A
6179545 Petersen, Jr. et al. Jan 2001 B1
Foreign Referenced Citations (1)
Number Date Country
2598362 Nov 1987 FR