Leveling ramp for a wheelchair

Abstract

An apparatus for providing wheelchair access to a vehicle, including a deployable wheelchair access assembly coupled to the vehicle and deployable to a position in which one end of the assembly is in contact with the ground. The wheelchair access assembly can include multiple panels. Some embodiments include a control system for adjusting the angular relationship of one panel relative to another panel. Yet other embodiments include a sensor for measuring the inclination of the deployed assembly relative to earth's gravity. In yet other embodiments the vehicle includes a sensor for measuring the inclination of the vehicle relative to earth's gravity, and a plurality of suspension actuators for changing the inclination of the vehicle.

1 .- 14 . (canceled) 
     
     
         15 . A multiwheeled ground vehicle having wheelchair access comprising:
 at least four wheels each supporting the vehicle from the ground by a suspension system, each suspension system including an actuatable spring in at least a portion of the load path from the corresponding wheel to the vehicle;   a first sensor providing a first electronic signal responsive to the inclination of said vehicle relative to ground;   a deployable wheelchair access assembly attached to the vehicle and including a platform adapted and configured for supporting a person on a wheelchair, said assembly being deployable from a stowed position within the vehicle to a deployed position extending out of the vehicle and in contact with the ground; and   a second sensor providing a second electronic signal responsive to a range of inclinations of the deployed wheelchair access assembly relative to ground; and   a controller receiving the second signal and operably connected to said wheelchair access assembly for control of said wheelchair access assembly between the stowed position and the deployed position.   
     
     
         16 . The vehicle of  claim 15  which further comprises a driver's compartment having an enunciator receiving the second signal and providing a visual indication or audio indication of the status of the deployed ramp. 
     
     
         17 . The vehicle of  claim 15  wherein said first sensor is located in the cab of the vehicle. 
     
     
         18 . (canceled) 
     
     
         19 . The vehicle of  claim 15  wherein the wheelchair access assembly is a foldable wheelchair ramp. 
     
     
         20 . (canceled) 
     
     
         21 . A multiwheeled ground vehicle having wheelchair access comprising:
 a vehicle body having a passenger door   a deployable multipanel wheelchair access assembly attached to said vehicle and including at least two panels adapted and configured to support a person in a wheelchair, said wheelchair access assembly being deployable from a stowed position within the vehicle to a deployed position extending out of the passenger door of the vehicle and in contact with a surface outside of the vehicle;   a sensor providing an electronic signal responsive to the position of one of said panels relative to the other of said panels; and   a controller receiving the signal and operably connected to said wheelchair access assembly for control of said wheelchair access assembly between the stowed position and the deployed position, said controller using the signal to adjust the relative angular position of one said panel relative to the other said panel to within a range of angles when in the deployed position.   
     
     
         22 . The vehicle of  claim 21  wherein said sensor provides a signal corresponding to the angular relationship of one section of said ramp relative to another section of said ramp. 
     
     
         23 . The vehicle of  claim 22  which further comprises a first actuator operated by said controller for deployment of said assembly and a second actuator operated by said controller for adjusting the relative angular position. 
     
     
         24 . The vehicle of  claim 23  wherein each said first actuator and said second actuator receive power for operation from the same source of power. 
     
     
         25 . The vehicle of  claim 24  wherein the source of power is hydraulic fluid. 
     
     
         26 . The vehicle of  claim 24  wherein the source of power is electricity. 
     
     
         27 . The vehicle of  claim 22  wherein said multipanel wheelchair assembly includes at least two substantially flat panels hinged together. 
     
     
         28 . (canceled) 
     
     
         29 . The vehicle of  claim 22  wherein said vehicle includes a ladder frame and said wheelchair access assembly is attached to said ladder frame. 
     
     
         30 . The vehicle of  claim 21  wherein said sensor is a first electronic sensor, and which further comprises a second electronic sensor providing a second electronic signal corresponding to the inclination of said vehicle body relative to the gravity of Earth. 
     
     
         31 . The vehicle of  claim 15  wherein the stowed position is substantially horizontal. 
     
     
         32 . The vehicle of  claim 15  wherein said deployable wheelchair access assembly includes at least two substantially flat panels movable relative to one another and each adapted and configured for supporting a person on a wheelchair. 
     
     
         33 . The vehicle of  claim 32  wherein said panels are hinged to each other, and said second sensor provides a second signal responsive to the inclination of one of said panels relative to ground 
     
     
         34 . The vehicle of  claim 15  wherein the vehicle includes a ladder frame having a pair of opposed, longitudinal members, and said deployable wheelchair access assembly is coupled to a longitudinal member of the ladder frame. 
     
     
         35 . The vehicle of  claim 15  wherein the controller provides a deployed position at a predetermined inclination relative to ground. 
     
     
         36 . The vehicle of  claim 15  which further comprises a driver's compartment having an enunciator receiving the first signal and providing a visual indication or audio indication of the inclination of the vehicle. 
     
     
         37 . The vehicle of  claim 15  wherein said suspension system includes a separately actuatable air spring supporting each wheel of the vehicle. 
     
     
         38 . The vehicle of  claim 15  wherein said first sensor provides an electronic signal responsive to the roll inclination of the vehicle. 
     
     
         39 . The vehicle of  claim 21  wherein said controller uses the signal to adjust the relative angular position of one said panel relative to the other said panel to substantial straight alignment when in the deployed position. 
     
     
         40 . The vehicle of  claim 21  wherein the stowed position is substantially horizontal. 
     
     
         41 . The vehicle of  claim 21  wherein said deployable wheelchair access assembly is coupled to a longitudinal member of the ladder frame. 
     
     
         42 . The vehicle of  claim 21  which further comprises a driver's compartment having an enunciator receiving the first signal and providing a visual indication or audio indication of the inclination of the vehicle. 
     
     
         43 . The vehicle of  claim 21  wherein said sensor uses the Hall effect in providing the electronic signal. 
     
     
         44 . The vehicle of  claim 21  wherein said sensor uses an LED in providing the electronic signal. 
     
     
         45 . The vehicle of  claim 21  wherein said sensor uses a contact switch in providing the electronic signal. 
     
     
         46 . The vehicle of  claim 21  wherein said sensor uses a variable resistance in providing the electronic signal. 
     
     
         47 . The vehicle of  claim 21  wherein said sensor uses a visual indicator. 
     
     
         48 . The vehicle of  claim 21  wherein said sensor uses a radiation source and a radiation detector in providing the electronic signal. 
     
     
         49 . The vehicle of  claim 21  which further comprises a first actuator operated by said controller for deployment of said assembly and a second actuator operated by said controller for adjusting the relative angular position.