Vehicle entrance ramp

The present invention relates to an extendible and retractable ramp device for a vehicle particularly concerned with the loading and unloading of handicapped person and which device particularly includes a power actuating mechanism disposed within the vehicle in such a way as to protect the mechanism from damage, provide a ramp structure conducive to non-interferring ingress and egress by handicapped passengers and to incorporate a disconnect device which permits the ramp to be extended or retracted manually in the event power actuating mechanism becomes inoperative.

BACKGROUND OF THE INVENTION 
The present invention relates to vehicle entranceways and exitways and, 
particularly, to stowable ramps associated therewith for facilitating the 
passage therethrough of wheelchairs and persons unable to negotiate one or 
more steps up into the vehicle. 
There has long been a need for an extendible ramp at the entranceway of a 
motor bus, for example, over which a wheelchair passenger or other 
handicapped person might traverse in entering or leaving the vehicle at a 
bus stop. Several years ago, Donald L. Manning was granted U.S. Pat. No. 
4,131,209 covering such an extendible ramp device. Mr. Manning and the 
inventor of the present device also filed a joint application Ser. No. 
831,305 Vehicle Entrance Ramp on Feb. 20, 1986 now U.S. Pat. No. 4,685,858 
as an improvement over Mr. Manning's earlier patent. 
A potential problem exists with the earlier ramp devices in that a failure 
of the ramp actuating power mechanism could disable the ramp from being 
extended or retracted. It is apparent that if the ramp cannot be retracted 
the vehicle could not be driven. Likewise if the ramp could not be 
extended it could be difficult to disembark wheelchair passengers. 
The present invention relates to a disconnect device which enables the ramp 
to be manually retracted or extended in the event the ramp actuating power 
mechanism becomes inoperative. More specifically, the device of the 
present invention disconnects the power driving mechanism from the ramp 
enabling the latter to be manually actuated. 
Prior Art 
The closest prior art of which I am aware are the already mentioned U.S. 
Pat. No. 4,131,209 Vehicle Entrance Ramp--Manning and pending application 
Ser. No. 831,305 filed Feb. 20, 1986 Vehicle Entrance Ramp--Hood and 
Manning. 
The following patents were cited during the prosecution of the earlier 
Manning patent and patent application: 
U.S. Pat. No. 1,717,303--Barclay 
U.S. Pat. No. 2,573,496--Runkle 
U.S. Pat. No. 2,797,104--Drobney et al 
U.S. Pat. No. 3,730,361--Haynes 
U.S. Pat. No. 4,022,337--Eichenhofer et al 
U.S. Pat. No. 4,027,807--Thorley 
U.S. Pat. No. 4,058,228--Hall 
U.S. Pat. No. 4,133,437--Gates 
U.S. Pat. No. 4,140,230--Pearson 
U.S. Pat. No. 4,306,634--Sangster 
U.S. Pat. No. 4,564,086--Kingston 
With the exception of Manning or Manning and Hood, none of the prior art 
references relates to a power actuated ramp. Drobney et al, Hall, Gates, 
Pearson, Sangster, Kingston, Eichenhofer and Thorley relate to power 
actuated steps or lifts and the related devices could not be negotiated by 
a wheelchair or traversed by any person who could not handle one or more 
steps. 
SUMMARY OF THE INVENTION 
It is among the principle objects of our invention to provide a power 
operated ramp to facilitate wheelchair passengers and the like in entering 
and leaving a vehicle, such as a motor bus; provide such a ramp which is 
normally stowed below the vehicle floor adjacent an entranceway to the 
vehicle and, when extended, moves outwardly through the entranceway and 
automatically tilts upwardly towards its inner end to provide a rigid 
inclined platform leading to the sidewalk or roadway exteriorly of the 
vehicle; to provide such a ramp whose extendible end portion is spaced 
below the vehicle floor to serve as a step for other persons entering the 
vehicle when the ramp is in its stowed position; to provide such a ramp 
including a normally vertical step riser in the vehicle entranceway which 
swings upwardly about the adjacent edge of the vehicle floor to cover the 
innermost end portion of the ramp when the latter is in its fully extended 
position; to provide a ramp actuating mechanism which is separate from the 
ramp and remains entirely inside the vehicle whereby such mechanism is 
prevented from being damaged or interfering with the use of the ramp by a 
handicapped passenger; and to provide a device for disconnecting the ramp 
from its power actuating mechanism so as to enable the ramp to be manually 
extended or retracted in the event the power mechanism becomes inoperative 
.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
As best seen by reference to FIGS. 1 through 4, a motor bus is indicated 
generally at 10 and includes a front passenger opening 12 generally 
opposite the driver's position and adapted to be closed by doors 14. In 
these views the bus is shown parked next to a curb and sidewalk area 
indicated at 16. An extendible ramp is indicated generally at 18 and is 
shown in FIGS. 1 and 2 in its fully extended position ready to receive a 
wheelchair or handicapped person. 
Referring specifically to FIG. 4, ramp 18 is shown in its fully retracted 
position beneath the vehicle floor 20. In this position, the outer most 
portion 22 of the ramp 18 is disposed within the front door entrance well 
and forms a step for normal movement into and out of the bus under 
conditions in which the use of the ramp is unnecessary. 
The bus includes a suitable subframe structure indicated generally at 24 
which supports the bus flooring and also supports and houses the ramp and 
its operating mechanism. 
The ramp and its operating mechanism will now be described in detail with 
particular reference to FIGS. 2 through 7. When the ramp is in its fully 
and partially stored positions beneath the vehicle floor, it is supported 
adjacent its laterally outer edges upon sets of roller devices 25, 26, 28 
and 29 which are, in turn, suitably mounted upon part of the vehicle 
subframe structure 24. A ramp driving screw is indicated at 30 and is 
supported for rotation within a housing indicated generally at 32 and 
which housing is, in turn, fixedly supported to the bus subframe 24. 
Housing 32 is best seen by reference to FIGS. 5, 6 and 7 and includes an 
upwardly opening, U-shaped channel 34 to which a drive screw supporting 
casing 36 is suitably fixed as by welding at its lower portion. The casing 
36 includes a tubular portion 38 within which drive screw 30 is rotatably 
supported. The upper side of casing 36 includes an upwardly opening 
channel portion 40 having a longitudinally extending slot 42. 
A traversing bracket member 44 includes inner guide elements 46 and 48 
disposed within said channel portion 40 and slot 42. Bracket 44 includes a 
downwardly opening U-shaped channel member 50 to the underside of which 
guide elements 46 and 48 are fixed. Guide elements 46 and 48 are suitably 
fixed to the U-shaped member 50 through screw members 52 and 54. The 
T-shaped guide elements 46 and 48 are longitudinally spaced relative to 
the bracket channel 50 so as to define an intermediate cavity 56 within 
which a rack member 58 is vertically slidably supported so as to project 
through a corresponding opening 60 in the tubular member 38 to engage with 
the threaded drive screw member 30. 
Rack member 58 is secured to a plate element 60 by screw member 62 and 64. 
A spacer 66 is disposed between rack member 58 and plate 60. 
The inner most end of drive screw 30 is drivably connected to an electric 
motor 74 through a suitable mechanism such as a pulley 76 and a belt 78. 
When motor 74 is energized to rotate screw 30, rack 58 is driven 
rearwardly or forwardly carrying with it bracket 44. 
The moveable bracket 44 is interconnected with the innermost end of ramp 18 
through a linkage mechanism indicated generally at 80. Linkage mechanism 
80 includes a pair of levers 82 pivotally connected on either side of the 
bracket respectively through pin members 84. The other ends of levers 82 
are connected through suitable brackets 86 to the innermost end of the 
ramp 18. As viewed in FIG. 4, as motor 74 is energized to extend ramp 18 
to its outer most position, drive screw 30 is rotated and drives bracket 
44 to the left and, in so doing, causes the levers 82 to impart a 
corresponding leftward movement to the ramp. 
A step riser is indicated generally at 88 and is hingedly secured to the 
bus floor 20 adjacent the step well. As the innermost end of ramp 18 
approaches riser 88 a suitable switch, not shown, is actuated to energize 
a power piston or solenoid device indicated at 90 pivotally connected to 
subframe 24 at 91. A bell crank 82 is pivotally supported at 94 to a 
portion of the floor substructure 24 and includes a first arm 96 pivotally 
connected to rod 98 of actuator 90 causing the bell crank to be rotated 
clockwise when the actuator is energized. The other arm 100 of bell crank 
82 includes a roller 102 at its outer end and which roller is adapted to 
engage ramp 18. As best seen in FIG. 2, when actuator 90 is energized to 
rotate the bell crank in a clockwise direction, the inner most end of ramp 
18 is elevated to bring said end into alignment with the bus floor 20 and, 
in so doing, also rotates the pivotal riser 88 to provide a smooth 
transition area between the ramp and the bus floor. When the driver wishes 
to retract the ramp, actuator 90 is de-energized causing the bell crank 
lever 92 to move in a counterclockwise direction and lowering the inner 
end of the ramp to a generally horizontal position after which motor 74 is 
again energized to move bracket 44 to the right and thereby retract ramp 
18 beneath the vehicle floor. 
With the aforedescribed arrangement, the ramp 18 is formed of an 
uninterrupted surface to provide an entirely smooth area for the ingress 
or egress of wheelchairs or handicapped people. At the same time, the ramp 
actuating motor and drive screw are disposed beneath the vehicle floor in 
a protected environment in a way as to minimize damage thereto. 
As best seen in FIGS. 5, 6, 7 and 8, a disconnect device includes a lever 
110, a cable 112 and an operating handle 114. Lever 110 is pivotally 
mounted on traveller 44 through a pin 116 threaded into spacer 66. Lever 
110 includes a pair of oppositely opening slots 118 and 120. A pair of 
studs 122 and 124 include threaded portion 126 and 128 respectively 
threadably connected to guide elements 46 and 48. 
Guide elements 46 and 48 respectively include enlarged bores 130 and 132 
within which coil springs 134 and 136 are respectively disposed and 
maintained in compression when lever 11 is in its normal or connected 
position as shown in FIGS. 6, 7 and 8. 
Lever 110 includes a laterally offset portion 138 to which the inner end of 
cable 112 is attached. The other end of cable 112 is connected to 
operating handle 114. An enlarged view of handle 114 is shown in FIG. 9 
and includes a casing 140 recessed into the upper surface of ramp 18. A 
handle tab 142 is pivotally connected to the upper end of a shaft 144 
rotatably supported within casing 140. Shaft 144 extends through and 
projects beyond the bottom surface of ramp 18. A lever 146 is suitably 
fixed, as by nut 148, to the lower end of shaft 144. The outer end of 
cable 112 is fixed to shaft lever 146. In its normal or inoperative 
position, tab is pivoted to its horizontal position so as to be recessed 
within casing 140 as shown in FIG. 9. 
As best seen in FIGS. 1 and 4, operating handle 114 is mounted toward the 
out end of ramp 18. Preferably and as best seen in FIG. 4, operating 
handle 114 is located so as to be laterally inside of the pivotal riser 88 
when the ramp is in its fully retracted position so that the handle is in 
a position where it is less likely to be damaged. It is obvious that the 
riser 88 may be lifted to gain access to operating handle 114. 
OPERATION OF DISCONNECT DEVICE 
For purposes of illustration, it will be assumed that the ramp-actuating 
power system becomes inoperative when ramp 18 is in its fully extended 
position as shown in FIGS. 1 and 2. In such case it becomes necessary to 
retract ramp 18 before the bus can be driven. 
Referring to FIG. 9, the first step is to rotate hold down screw 141 to 
unlock handle tab 142 the inner end of which is pushed down thereby 
causing the outer end of the tab to lift to a generally vertical or 
upright position. Next, tab 142 is rotated in a clockwise direction which 
causes a similar rotation of shaft 144 and lever 146. The rotation imparts 
a leftward movement of cable 112. 
As best seen in FIGS. 5 through 8, leftward movement of cable 112 causes a 
counterclockwise rotation of disconnect lever 110. As seen in the dash 
lines of FIG. 8, counterclockwise movement of lever 110 moves the latter 
from beneath the heads of studs 122 and 124. Once lever 110 is free of 
studs 122 and 124, springs 134 and 136 bias plate 60 upwardly until it 
abuts against the underside of the heads of studs 122 and 124. Such upward 
movement lifts rack member 58 out of driving engagement with screw 30 
thereby disconnecting the power driving mechanism from ramp 18. As already 
noted, when actuator 90 is de-energized, as by shutting off the electric 
power, the bell crank lever 92 will move in a counterclockwise direction 
to lower the inner end of ramp 18. Thus, with the power mechanism 
disconnected from the ramp and the inner end of the latter lowered, the 
ramp can be manually pushed to a retracted position enabling the bus to be 
driven. 
When it is desired to reconnect the power mechanism to the ramp plate 60 
and lever 110 are depressed against the force of springs 134 and 136 and 
lever 110 is rotated in a clockwise direction whereby the lever is once 
again disposed beneath and vertically restrained by the heads of studs 122 
and 124. In this position rack member 58 is once again threadably 
connected to drive screw 30. It is necessary to perform the reconnecting 
operation with ramp 18 in its fully extended position because the ramp can 
be lifted to give manual access to disconnect lever 110 for both rotation 
and depression. 
It will be appreciated that various minor changes in the parts or their 
arrangement may be made without departing from the scope of the inventions 
as herein after claimed.