Note: Descriptions are shown in the official language in which they were submitted.
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MECHANISM FOR STOWING AND DEPLOYING
A CARRIAGE WITH RESPECT TO A TRUCK BOIL
This invention relates generally to the transportation industry, and has to do
particularly with improvements in a truck-mounted mechanism adapted to move a
load-bearing carriage between a stowed position and a deployed position.
BACKGROUND OF THIS INVENTION
Numerous attempts have been made to provide, typically for a pick-up truck,
a carriage which fits into the rear box when stowed, and which is associated
with a
mechanism by which the carriage can be removed from the truck box and set down
upon the same surface as that supporting the truck. Such carriages range in
use
from garbage collecting to the transportation of vehicles such as skidoos or
of bulk
materials. Generally, the prior art has attempted to over-engineer the various
frame
members supporting the carriage during its movement, often utilizing several
parallelogram linkages, winches and cables, and thus having to deal with the
problem of disengaging complex supporting linkages from the carriage, once the
carriage is on the ground.
Because of this complexity, these prior carriage-handling mechanisms have
been expensive, unreliable and time-consuming to install and maintain, as well
as
requiring professional operators trained on the sequencing of various
controls,
sometime in unison, during carriage retraction and deployment.
GENERAL DESCRIPTION OF THIS INVENTION
In view of the above-mentioned shortcomings of the prior art, it is an object
of one aspect of this invention to provide a carriage control mechanism which
utilizes only a single arm that is easily attached to or detached from one end
of the
carriage. The other end of the carriage is free to move in any direction, but
is
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constrained by guide rolls to movement which is essentially parallel with the
travel
direction of the truck. Because the transfer arm is of such simple
construction, the
apparatus to be described herein is inexpensive, easily mounted and serviced,
and
reliable to operate.
More particularly, this invention provides, in combination:
a carriage having a front end and a rear end,
a receptacle for receiving said carriage,
a transfer arm having a first end pivotally mounted with respect to said
receptacle and a second end pivotally engaging the front end of the carriage,
the arm
being movable between a carriage-stowed position wherein the carriage is
received
by the receptacle, and a carriage-deployed position wherein the carriage is
external
to the receptacle,
roller guide means mounted on the receptacle,
track means under the carriage for engaging the roller guide means,
wheel means mounted on the carriage adjacent the rear end thereof,
and power means for positively moving the transfer arm between its said
positions,
whereby, as the transfer arm begins to move away from the carriage-stowed
position, the front end of the carriage lifts upwardly while the carriage
moves
rearwardly, supported and guided by the roller guide means, until the wheel
means
contacts a surface lying below the level of the pivot at the first end of the
transfer
arm, whereupon the track means disengages from the roller guide means, and the
carriage comes to a stop resting on said surface.
Further, this invention provides, a method of deploying from an open-
topped receptacle a carriage having a front end and a rear end, said method
comprising the steps:
providing a transfer arm having a first end pivotally mounted with respect to
said receptacle and a second end pivotally engaging the front end of the
carriage, the
arm being movable between a carriage-stowed position wherein the carriage is
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received by the receptacle, and a carriage-deployed position wherein the
carriage is
external to the receptacle, the receptacle having roller guide means mounted
thereon, the carriage having track means thereunder for engaging the roller
guide
means, the carriage further having wheel means adjacent the rear end thereof,
and utilising power means to positively move the transfer arm between its said
positions, such that, as the transfer arm begins to move away from the
carriage-
stowed position, the front end of the carriage lifts upwardly while the
carriage
begins to move rearwardly, supported and guided by the roller guide means,
until
the wheel means contacts a surface lying below the level of the pivot at the
first end
of the transfer arm, whereupon the track means disengages from the roller
guide
means, and the carriage continues to move rearwardly until it comes to a stop
resting on said surface.
GENERAL DESCRIPTION OF THE DRAWINGS
One embodiment of this invention is illustrated in the accompanying
drawings, in which like numerals denote like parts throughout the several
views,
and in which:
Figures 1 through 6 are schematic side elevational views of a portions of a
truck box, a carriage being loaded into or out of the truck box, and a
transfer arm
which causes movement of the carriage;
Figure 7 is a schematic elevational view of a truck, showing the major
components of the mechanism to be disclosed herein; and
Figure 8 is a side elevational view of one possible mechanism for controlling
the position of the transfer arm during stowing or deployment of the carriage.
DETAILED DESCRIPTION OF THE DRAWINGS
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Attention is first directed to Figure 7, which shows a truck generally at 10,
the truck having a cab 12, a box 14, and wheels 16. The truck rests on a
surface
18.
Juxtaposed within the box 14, (which will be called hereinafter a receptacle)
is a carriage 20. The carriage 20 in Figure 7 is shown with only its basic
structural
parts, namely a bottom surface 22, a front vertical wall 24, a hook-shaped
member
26 at the top of the vertical wall 24, and a pair of laterally separated
wheels 28 at
the rearward edge of the carriage 20.
The truck frame includes a horizontal member 30, which supports an upright
portion 32 at the top of which are provided two spaced-apart roller guides 34.
The
carriage 20 includes, mounted under the bottom surface 22, a pair of tracks 35
separated by the same distance that separates the roller guides 34, so that
the tracks
can ride in the roller guides during stowing or deployment, as will be evident
from
what follows.
Pivoted with respect to the frame 29 is one end 36 of a transfer arm 38, the
latter being geniculate at the location 40, extending upwardly therefrom to an
upper
edge which defines a bar 42 adapted to be engaged by the hook-shaped member 26
of the carriage 20.
Mechanical/hydraulic means is provided to rotate the transfer arm 38 in the
clockwise direction from that shown in Figure 7, turning about the pivot
location
37, and initiating rearward movement of the carriage as the transfer arm
starts to
pivot.
The actual motion of the carriage throughout the process of being removed
from the receptacle 14 and set upon the ground 18 is clearly shown in Figures
1-6,
to which attention is now directed.
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Figure 1 shows the stowed position of the carriage 20, and thus represents
the same position as that shown in Figure 7. It is to be emphasized that the
truck
portion which receives the carriage when stowed can be other than the box of a
pick-up. For example, the bed of a flatbed truck could also serve as the part
5 accommodating the carriage.
In Figure 2, the transfer arm has rotated approximately 35°
clockwise, and
as can be seen, the carriage has started to move rearwardly and to rotate in
the
clockwise direction as it does so.
This motion continues until the wheels 28 at the rearward end of the carriage
touch the surface 18, as seen in Figure 3. At this point, the carriage
disengages
from the supporting roller guides 34 and begins to rotate in a counter-
clockwise
direction as the transfer arm 38 continues its clockwise motion, the wheels 28
now
15 rolling rearwardly and taking a part of the weight of the carriage.
Shortly, the
mechanism reaches the stage illustrated in Figure 4, where the carriage is
approaching its final position. The latter is shown in Figure 5, with the
carriage 20
resting on the surface 18. By moving the transfer arm slightly further in the
clockwise direction, as seen in Figure 6, the bar 42 at the end of the
transfer arm 38
20 disengages from the hook shaped member 26. The truck can now be driven
ahead,
leaving the disengaged carriage 20 on the surface 18. At the same time, the
transfer
arm 38 would normally be rotated counter-clockwise back to its original
position as
seen in Figure 1, thus being largely out of the way of other items in the
truck box.
Figure 8 shows one possible mechanical/hydraulic mechanism for moving
the transfer arm 38 about the pivot location 37.
The main member of the mechanism shown in Figure 8 is an intermediate
lever 50 of which one end is pivoted at 52 to a supporting framework secured
to the
truck. The other end is pivoted at 54 to one end of a connecting link 56, the
other
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end of the link 56 being pivoted at 58 to a bracket 60 which is secured to and
moves
with the transfer arm 38.
A hydraulic cylinder 62 is provided, hinged at the point 64 to the supporting
framework secured to the truck. The cylinder 62 houses a piston (not seen) to
which is connected a rod 68 pivotally connected at 70 to an intermediate point
on
the intermediate lever 50.
It will thus be seen that, as the hydraulic cylinder pushes the rod 68
leftwardly, it will cause the intermediate lever 50 to pivot counter-clockwise
about
the pivot point 52, thus pulling leftwardly on the connecting link 56, which
in turn
causes the transfer arm 38 to rotate counter-clockwise about its pivot
location 37.
When the transfer arm 38 reaches the position shown at 38a in Figure 8 (drawn
in
broken lines), the connecting link 56 will have moved to the position shown at
56a
in broken lines, while the intermediate lever 50 will have moved along the arc
shown by the arrow 81. The intermediate lever is not shown in the
corresponding
position, in order to avoid cluttering the drawing.
In Figure 7 can be seen a lock device 73, which includes a finger 75 on the
frame 29 which engages above a finger 77 under the carriage 20, when the
carriage
is in its stowed position (that of Figure 7).
While one embodiment of this invention has been illustrated in the
accompanied drawings and described hereinabove, it will be evident to those
skilled
in the art that changes and modifications may be made therein without
departing
from the essence of this invention, as set forth in the appended claims.
