Material or article handling – Self-loading or unloading vehicles – Loading or unloading by other carrier or mover means – and...
Reexamination Certificate
1999-08-17
2001-10-30
Bratlie, Steven A. (Department: 3652)
Material or article handling
Self-loading or unloading vehicles
Loading or unloading by other carrier or mover means, and...
C414S550000, C414S921000
Reexamination Certificate
active
06309170
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns a lift mechanism for transferring a load between laterally adjacent supporting surfaces at different elevations, especially for moving a load in either direction between a vehicle compartment and the ground alongside the vehicle. The lift mechanism permits different relative motions which are effected alternately or successively when stowing, deploying and moving a platform that supports the load, especially a wheelchair, to be moved back and forth between the passenger compartment of a vehicle such as a van, bus or light truck, and the ground adjacent to such vehicle.
The lift has a substantially vertical fixed frame rigidly mounted to span a vehicle doorway. A partial frame is mounted to move up and down relative to the fixed frame. The partial frame is engaged with the fixed frame when the partial frame is in the upper or retracted position, namely via interengaging protruding and receptacle members at each corner of the fixed and partial frames, which interengaging members position the partial frame relative to the fixed frame and mechanically support the partial frame on the fixed frame. The pivoting frame supports a platform and has vertical and horizontal pivot axes whereby a movable platform can swing into or out of the plane of the doorway on a vertical hinge axis; and the platform can be shifted on a horizontal pivot axis between a vertical stowed position and a horizontal deployed position in which the platform can support a wheel chair or the like.
Using the foregoing frames and hinging or pivoting mountings, the whole lift mechanism can be retracted into a substantially vertical position in which the platform is pivoted up and resides in the doorway. The partial frame can be moved up and down from the doorway, carrying along the pivot frame and platform. When the platform is pivoted up, the pivot frame can be hinged open or shut on the vertical axis. When the pivot frame is hinged shut on the vertical axis the platform can be pivoted down into its horizontal supporting position. These superimposed degrees of freedom of motion are possible because the pivoting frame is carried on a very substantial vertical hinge post, and the partial frame is mechanically engaged in, and partially supported by the fixed frame when raised into the retracted position. The lift thus comprises portions that can be can be hinged open vertically to clear the doorway for passing into and out of the vehicle through an open doorway, or hinged closed across the doorway. The lift further comprises a platform that pivots down to provide a wheel chair support or up for compact stowing. With the platform pivoted down to the supporting position, the partial frame can lift or lower the platform on linkages. The platform thereby raises a wheel chair supported on the platform to the elevation of the vehicle interior floor, or lowers a wheel chair supported on the platform from the vehicle floor to the ground.
The pivoting frame is carried on the partial frame and the partial frame is carried on a parallelogram linkage for guiding the partial frame up or down through an arc, while holding the partial frame parallel to the fixed frame in the doorway. This partial frame supports a platform that is pivotally coupled to the partial frame on a horizontal pivot axis. The platform is pivoted on the horizontal axis to an orientation parallel to the ground and perpendicular to the partial frame, when supporting a load such as the wheelchair. The platform is movable with the partial frame on the parallelogram linkage, from the vehicle compartment level to the ground level, being kept horizontal by the parallelogram linkage. Roll-off gates, barriers and hand holds are provided for safety.
In the reverse order, the platform can transfer a wheelchair from the ground level to the vehicle compartment, whereupon the safety gates and barriers permit the wheelchair to roll into the vehicle. The platform is pivoted up on the horizontal axis, thus moving each of the platform, the partial frame and the pivoting frame into the plane of the fixed frame for compact storage. In this position the mechanism, except for the fixed frame and partial frame, can be unlatched and pivoted clear of the doorway opening.
Accordingly the apparatus has at least three distinct modes of movement. In one mode, the parallelogram linkage holds the platform in a horizontal orientation as the platform is raised or lowered between ground level and the level of the vehicle passenger compartment, opening the movable gates or barriers to permit the wheelchair to roll onto and off of the platform at either level.
In a second mode, the platform is pivotable on a horizontal axis with the movable chassis (i.e., the partial frame) on the inboard side of the platform. The platform can be pivoted on this axis and raised from its horizontal wheelchair-carrying orientation to a vertical orientation. With the platform vertical and the movable chassis retracted, the elements of the mechanism are substantially coplanar with the doorway and the fixed frame. Thus the entire mechanism resides across the vehicle doorway.
The platform is mounted on the movable vertical chassis members by a heavy duty journal post on one lateral side and by a heavy duty clamping latch on the other lateral side. By opening the clamping latch the platform (preferably as folded upwardly into its stowed position), the platform can be swung, in a third mode, clear of the doorway in the manner of a hinged gate frame.
The movable roll-off gates, handrail members and doorway plane barriers for safety purposes preferably are linked and structured for automatic deployment when the platform is in the position where such gates, members and barriers are useful, and for retraction otherwise. For this purpose the handrail members and doorway plane barriers preferably are coupled mechanically to the platform and the parallelogram linkage, respectively. A roll-off gate is provided at each opposite side of the platform. On the inboard side the gate is lowered by a roller contacting the base of the fixed frame at the sill of the vehicle doorway and comprises a transition ramp that is lowered against the base of the fixed frame as the gate is lowered. On the outboard side a similar roller lowers the opposite gate when contact is made with the ground. At least on the outboard side a position latch captures the gate mechanism until lifted by contact between the roller and the ground. As a result, the roll-off gate cannot be opened inadvertently by rolling the wheelchair against it when the platform is not on the ground.
More particularly, a mounting structure having laterally-spaced fixed vertical posts is rigidly mounted in the vehicle doorway, inside the innermost (closed) position of the vehicle outer door, leaving clearance for the outer door hinges and latch mechanism. The fixed vertical posts preferably extend from the vehicle floor to the roof. An upper horizontal header and a lower horizontal base or sill are disposed around the doorway or a portion of the doorway, and frame the doorway together with the vertical posts. The laterally spaced vertical standards of the movable chassis are attached to the fixed posts by a parallelogram linkage, namely at least two parallel pivot arms pivotally affixed to the fixed posts and vertical standards such that the standards remain parallel to the fixed posts. Preferably such a parallelogram linkage is provided at each lateral side of the lift.
The movable standards reside against the fixed posts in the retracted position of the lift. The parallelogram linkage collapses when the standards are retracted inboard and opens when the standards are deployed outwardly and downwardly to lower the lift. In this manner the parallelogram linkage(s) keep the movable standards parallel to the fixed frame (substantially vertical) and keep the wheel chair supporting platform horizontally oriented when deployed.
The platform is attached to the movable vertical standards on a horizontal hinge axis e
Bratlie Steven A.
Duane Morris & Heckscher LLP
LandOfFree
Vehicle wheelchair lift with mutually perpendicular pivot... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vehicle wheelchair lift with mutually perpendicular pivot..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vehicle wheelchair lift with mutually perpendicular pivot... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2572754