Material or article handling – Self-loading or unloading vehicles – Loading or unloading by other carrier or mover means – and...
Patent
1988-11-02
1990-06-05
Werner, Frank E.
Material or article handling
Self-loading or unloading vehicles
Loading or unloading by other carrier or mover means, and...
187 9R, B60P 144, B66B 904
Patent
active
049309714
DESCRIPTION:
BRIEF SUMMARY
The invention relates to lift platforms for road vehicles for loading and unloading facilities for vehicles and trailers, such lifting platforms, usually fitted at the rear of the vehicle are well known.
Two types are in general use: one is a cantilever type which is usually fitted to the vehicle chassis frame and elevates from ground level to the vehicle floor, the other type is called a column lift. The column lift generally has a structural member, generally in the form of a square or rectangular hollow section with a lengthwise slot one one face. One such column is fitted vertically at each side of the vehicle with the slots facing inwardly of the vehicle rear opening. In each column a sliding member is located, the sliding member having rollers spaced some distance apart. Each sliding member is attached to the platform in a hinged manner so that when not in use, the platform can be locked in a vertical position.
Traditionally means are generally provided to provide oil pressure to a single acting hydraulic cylinder which is normally located transversely, horizontally either under the floor of the vehicle body or on the roof of the body. Wire ropes or chains are fitted around pulleys with one end of each wire rope or chain being attached to the two sliding members, with the other end secured to the body structure.
By the nature of the design of this type of actuating system a complex system of wire ropes and pulleys is required to provide the elevating means to the lift platform.
One object of the invention is to provide a lift platform for a vehicle with a reduced number of working parts which will be more reliable and more readily servicable.
According to the invention there is provided a lift platform for location at the rear of a road vehicle comprising a horizontally extending platform member movable vertically between one or more vehicle floor levels and substantially ground level, two oppositely acting fluid actuated rams located vertically one on each interior side wall adjacent the rear of the vehicle, fluid pressure being connected to be fed via one ram to the other to ensure equal movement of both rams in opposite directions, the rams being connected by wire ropes or chains via pulleys, to the platform member and fluid equalising means being connected between said rams for adjusting the horizontal level of the platform member.
Preferably a first pulley is attached adjacent each end of the piston of each ram and a second pulley is mounted adjacent the roof of vehicle on each side thereof each with its axis of rotation being horizontally offset with respect to the respective first pulley, respective wire ropes or chains being connected at one end thereof to respective slider members attached to the platform member and passing over the second pulleys and under the first pulleys to be connected respectively to adjacent the roof of the vehicle on the side of vehicle with the ram with the downwardly acting piston and to the cylinder of the ram on the side of the vehicle with the upwardly acting piston, such said movements of the ram pistons being for causing upward movement of the platform and being reversible for downward movement of the platform.
Furthermore the fluid pressure connection to said one ram may be closed by closing a valve adjacent the input thereto and may be connected via a further valve to said other ram for levelling of the platform member.
The further valve may comprise a needle valve to enable fine control of the levelling of the platform member.
Further fluid actuated rams may be connected one between each slider member and its respective side of the platform member for moving the platform member between horizontal and vertical positions. All of the fluid actuated rams are preferably actuated by hydraulic fluid.
The foregoing and further features of the invention may be more readily understood from the following description of a preferred embodiment thereof, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a diagrammatic rear elevational vie
REFERENCES:
patent: 2106878 (1938-02-01), Sinclair
patent: 2701654 (1955-02-01), Williamsen
patent: 2906374 (1959-09-01), Brumby
patent: 3048283 (1962-08-01), Phillips
patent: 3240369 (1966-03-01), Kappen
patent: 3777853 (1973-12-01), Miller
patent: 4467894 (1984-08-01), Sinclair
patent: 4499971 (1985-02-01), Luebrecht et al.
patent: 4579500 (1986-04-01), Robinson
patent: 4638886 (1987-01-01), Marietta
Katz Robert S.
Werner Frank E.
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