Cargo handling ramp

A cargo handling ramp including a support frame and an inclined walkway provided with hand rails along the walkway and rollers beneath the frame for moving it over a surface wherein a mechanism is provided for raising and lowering the lowermost end of the walkway relative to the upper end of the walkway to adjust the incline of the walkway for use of the device in loading operations and wherein a rub rail type brake is provided to control rate of descent of wheeled standard size cartons or containers down the ramp to avoid dangerous situations.

FIELD OF THE INVENTION 
This invention relates to cargo handling and more particularly to a ramp 
for use in loading and unloading cargo from vehicles. 
BACKGROUND OF THE INVENTION 
In the past there have been numerous problems involved in loading and 
unloading cargo on, for example, aircraft or trucks. This invention is of 
an improved ramp for use in loading and unloading such equipment with 
standard size containers for cargo. 
SUMMARY OF THE INVENTION 
It is a general object of this invention to provide an improved cargo ramp 
which includes an inclined walkway which is adapted to be tilted to raise 
and lower the lower end relative to the upper end and wherein a brake 
mechanism is provided to control downward movement of wheeled standard 
size containers on the walkway and wherein the device is an overall 
improvement of those heretofore used in the trade.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIG. 1, the cargo ramp 2 is illustrated in use with an 
aircraft 3 and a truck 4. As seen in FIG. 2, the ramp is composed of a 
support frame 5 which has an elevated or higher end 6 and a lower end 7. 
This frame supports an inclined walkway 45. The frame is provided with 
spaced depending outwardly, downwardly diverging support legs 75 which are 
braced by members 77 with the legs 75 and 77 terminating the coplanar 
relation and being rigidly connected as by welding to lower frame portion 
71 that is normally in a generally horizontal attitude. The lower frame 
portion 71, and the lift in FIG. 2, at the elevated end 6, is provided 
with a pair of roller means 23. Similarly, the lower end at the right of 
FIG. 2 is provided with a pair of roller means 25. These roller means 
permit the ramp to be easily rolled into position for use. A tow bar 31 is 
also provided for this purpose. 
The walkway 45 is preferably covered with a friction surface as 
illustrated. Further, with reference to FIG. 3, it is seen that the 
walkway is composed of a floor which is supported on an upper frame 
structure. This upper frame structure is composed of coplanar frame 
members 73 that define the inclined plane and which join the upper ends of 
the support legs 75. Longitudinally extending runners 48 (FIG. 11) are 
also provided along the under portion of the floor or walkway 45. 
Along the walkway, a handrail structure 33 is provided, as shown in FIG. 3. 
As best shown in FIGS. 17 and 12, downwardly extending legs, 33' are 
received in telescoped relation within in sockets 34. These sockets are 
welded at spaced locations along the edges of the upper frame structure 
73. Also along these edges upstanding guide plates 47 are provided. 
At the elevated end at the left in FIG. 3, a flap 43 is provided which has 
a support 44. It is hingedly connected as at 49 to the upper frame 
structure. At the lower ramp end, the walkway terminates at a portion 
which is not inclined and which is provided with hand rails 35 and 37, 
there being a gap in the handrail 37 for access by means of a ladder 51. 
Preferably a hingedly connected ramp extension 39 with a pair of support 
cables 41 are also provided at the lower end. 
Once the ramp has been moved into position for use, as in FIG. 1, it is 
fixed in that position by a structure now to be described. Also, in use, a 
mechanism permits the lower end of the ramp to be raised or lowered as 
will also be described. 
Referring to the left of FIGS. 2 and 3, a position loading means is 
provided, at the elevated end, beneath the frame lower portion, including 
a pair of feet 27. These feet are connected by a pivot arm 28 to pivot 
connections 30 on the frame lower portion 71, see FIG. 3. The feet may be 
raised or lowered by use of the piston 21 which is hydraulically connected 
to a pump 100 energized by a battery 102 and operated by controls 101. 
When the ramp has been positioned for use, the piston is operated to lower 
the feet, see the FIG. 2 position. It thus cannot roll out of position. 
At the lower end, a similarly structured slope adapting means is provided 
which includes piston 21, link arm 28, and pivot connection 30. Roller 
means 29 are provided on the ower end link arm 28 actuation of piston and 
link arm combination 21, 28, such as shown in FIG. 2, causes upward 
movement of the lower end of the walkway. 
It is thus seen that when in position, the incline or slope of the walkway 
may be adjusted by raising or lowering the lower end. For example, if 
relatively heavy containers are to be rolled up the walkway, the lower end 
is raised to adjust the angle of slope of this walkway. 
The device also includes a cargo brake mechanism so that weeled containers 
do not run wildly and dangerously down the walkway. This mechanism 
controls the rate of movement of such containers in a manner now to be 
described. The brake mechanism or control mechanism will best be 
understood on reference to FIGS. 11, 12 and 13. First as to structure, the 
brake mechanism is composed of a pair of rub rails 53, preferably provided 
with a rubbery outer cargo container contacting surface 54. The rub rails 
are carried on pivotal pairs of depending support legs, see FIG. 13. 
Preferably these are two pairs of long ones 55 and three pairs of short 
ones 57. As shown in FIG. 12, the lower ends of these pivotal legs are 
pivotally connected to the upper frame structure as at the clevis 58 
connected to the frame by pivot pins 60 secured by a cotter pin 61. Thus, 
as seen in FIG. 13, the rub rails are pivotal into and out of partial 
blocking relation of the walkway. The rub rails are normally urged 
inwardly by tension springs 70 which pull the lower end of the longer legs 
outwardly with respect to the lower portion 71 of the frame, pivoting the 
rub rails toward one another and thereby constricting the walkway passage. 
Tension adjusting means are provided in the form of screws 72 for these 
springs. Means are also provided to relieve the brake i.e., retract the 
rub rails. This means will best be understood in reference to FIG. 13 on 
which arrowed lines have been applied to aid in following the description 
of the mechanism. On the lower frame, bell crank means 67 are pivotally 
supported on vertical pivots. A link 68 connects these bell cranks so that 
they operate together. The bell cranks are adapted to be turned by the 
following mechanism using the operator 59. The operator 59, accessible on 
the walkway adjacent the lower end, is keyed to a bar 62 so that rotation 
of the bar swings the arm 63 to raise or lower the vertical bar 64 thereby 
rotating the link 65 and pulling the arm 66 which in turn pivots the bell 
crank 67. Because the ends of this crank 67 are pivotally connected to the 
links 69 and the lower ends of the longer support legs 55, the rub rails 
can be pivoted to retract them from the normal braking position. It is 
thus seen that in this manner the rate of descent or movement of wheeled 
cargo containers can be controlled. 
FIGS. 5-10 illustrate a somewhat modified lower end of an alternative 
embodiment. This embodiment provides a lift at the lower end. It includes 
a scissor mechanism 91. It is operated on movement of a hydraulic piston 
21. The lower frame portion and the upper frame structure are each 
provided with guide tracks 93 for rollers 95 on the upper and lower legs 
of the scissor mechanism as they move in scissor fashion with respect to 
the scissor mechanism leg pivot 94. In this embodiment the lift 
accommodates loading of the lower end of the ramp from a ground supply of 
cargo. 
While the instant invention has been shown and described herein in what is 
conceived to be the most practical and preferred embodiment, it is 
recognized that departures may be made therefrom within the scope of the 
invention, which is therefore not to be limited to the details disclosed 
herein but is to be accorded the full scope of the claims so as to embrace 
any and all equivalent apparatus and articles.