05180275 is referenced by 89 patents and cites 9 patents.

Passive rotary wheelchair lift that is retrofittable in transit vehicles on either the forward or rearward edge of a side double-door step well. The lift employs in its preferred embodiment a double slide tube having a box frame with a cross header. A hydraulic cylinder actuates a pair of chains, one descending down each lift tube to operate the vertical lift. A manual hand pump is provided in the case of power failure. Secured to the bottom of inner telescoping lift tubes is a plate carrying a power actuator for rotating the lift platform from a deployed horizontal position to a vertical stowed position. In the stowed position the platform is approximately 26 inches in length and 36 inches in width. The platform has one or more slide-mounted extension sections which permit the platform to extend out to a full 51 inches. Manual or power-actuated wheel stops are provided at the rear entry and the forward end, for either one way or two way entry/exit onto the platform. Lockout circuitry prevents the actuators from rotating or stowing if the platform is not in its full raised position. Actuator clutch mechanism prevents the platform from being stowed if it is occupied. As installed, one of the double doors is openable permitting the stairwell to be used by an able-bodied person. The stowed platform is nested against a transit seat and remains behind the closed door half of the double-door pair. For use by a wheel chair user, both doors are opened and the lift is deployed, rotated and actuated to raise or lower the user to the ground, platform or curb. A special power actuating and ground contact locking plate is employed to permit the entry the entry wheelstop to be both power actuated and pivoted to the stowed position. The actuators can be disconnected for full manual operation in the event of power failure. A variety of lockout switches and circuitry is shown.

Title
Rotary bus lift with power stowable platform
Application Number
7/706583
Publication Number
5180275
Application Date
May 28, 1991
Publication Date
January 19, 1993
Inventor
Kevin L Crawford
Winamac
IN, US
Ronald W Goodrich
Logansport
IN, US
Edward A Czech
Winamac
IN, US
Agent
Thomas C Feix
Jacques M Dulin
Assignee
The Braun Corporation
IN, US
IPC
B60P 1/00
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