Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~ 2 ~
~ ~,
TARP ROLL SAFETY SYSTEM FOR TR~ILERS
Field of the Invention
This invention relates to the field of covers for trailers and in particular to a system
for rolling and unrolling tarp covers used to cover chip trailers and the like for transport by means
of a tractor in a tractor trailer combination, wherein an operator can roll and unroll the tarp cover
from the ground.
0 Background of the Invention
Conventional open-top trailers such as chip trailers used to convey wood chips, are
covered by flexible sheets such as tarps. In the prior art, a platform is typically provided at one
end of the trailer so that an operator may climb up onto the platform to manually roll and unroll
the tarp so as to uncover and cover, respectively, the trailer opening. In practice, however, an
operator quite often is required to climb up onto the loaded trailer to assist the rolling and
unrolling the tarp cover. This has resulted in accidents where, for example, in the winter time and
in the dark, an operator who is expected to cover and uncover the load by himself, will slip and
fall from the top of the trailer. The fall is a significant distance, often in resulting in injury.
Consequently, it is desirable, and an object of the present invention to provide, a
system which relieves the practice requirement of an operator having to climb up onto, firstly, a
platform elevated above the ground, and secondly, the load itself to assist rolling and unrolling the
tarp cover. It is an obJect ofthe present invention to provide such a system where an operator can
2 5 more safely roll and unroll the tarp cover from the ground.
In the prior art, applicant is aware of United States patent No. 5,549,347 whichissued to Anderson on August 27, l 996, for An All Weather Mechanically Reciprocatable Roll
2 ~ ~ 2 ~ ~ ~
."_
Tarp Cover Apparatus. Anderson teaches a mechanically reciprocatable roll top cover for
covering and uncovering the open top side of receptacles such as trailers. The panel is divided
into two sloping panels by a truss structure. Two primary operating drive devices are provided
which include an uncovering drive device for removing the cover and a covering drive device for
replacing the cover. The cover has one edge fixed at one side wall of the trailer receptacle. The
opposing edge of the cover is free to travel between the opposing side walls of the trailer
receptacle. The uncovering drive device includes a shaft which is rotated toward the cover's fixed
edge to wind the cover onto the shaft. The covering drive device is a shaft rotatably mounted to
the opposite side wall of the trailer. A plurality of flexible straps and a strap winding system are
0 mounted to the shaft. The straps interconnect the shaft to the free edge of the cover so that when
the shaft is rotated, the straps draw the cover over the truss structure. The straps are wound onto
spools mounted on the shaft.
In the tarp cover unrolling system of the present invention, there is no requirement
for a rotatable shaft having spools mounted thereon cooperating with straps attached to the cover
so as to draw the cover across the receptacle opening. Rather, the system of the present invention
incorporates a harness which is rolled up along with the tarp when the tarp is rolled. The harness
is attachable to a length of line which may be pulled by the operator from the ground so as to
unroll the tarp and thereby cover the trailer opening.
Summarv of the Invention
The trailer cover deployment and storage device of the present invention includes,
without limiting, means for selectively deploying a flexible cover over an upwardly open trailer
2 5 opening9 where a first longitudinal edge of the flexible cover is mounted along a first longitudinal
edge of an upper, generally planar opening of the trailer.
The trailer includes at least one lateral spanning member extending from the first
longitudinal edge of the generally planar opening to an opposed second longitudinal edge of the
planar opening for supporting thereon the flexible cover when deployed and during deployment.
The flexible cover is sized so that an opposed second longitudinal edge of the
flexible cover opposed to the first longitudinal edge of the flexible cover overlaps the second
longitudinal edge of the planar opening when the flexible cover is deployed.
The second longitudinal edge of the flexible cover has a rigid member mounted
therealong. The flexible cover is retractably deploya~le from a furled or rolled-up storage position
along the first longi~l-1in~1 edge of the planar opening. The flexible cover is furled or rolled about
a longitudinal axis of the rigid member. The cover is rolled from the second longitudinal edge,
over the spanning member or members, and any load held in the trailer, to the first longitudinal
edge. A harness, which may be a "V"-shaped pair of ropes or a like flexible member has opposed
first and second ends. The spaced apart ends of the "V" may be thought of as the second end of
the flexible member. The second end of the flexible member is mounted to a mid-point along the
second longitudinal edge of the flexible cover. The harness is sized so as to be positionable
laterally from the second longitudinal edge to the first longitudinal edge of the flexible cover,
across, so as to lay on and extend laterally from, an upper surface of the flexible cover when the
2 o flexible cover is unfurled or unrolled so as to be deployed across the planar opening. When the
flexible cover is furled or rolled-up the harness is correspondingly furled or rolled-up in contact
with the upper surface of the flexible cover in the storage position. An elongate flexible lead, such
as a throw line is releasably securable at the first end of the harness. The free end of the throw line
and the free end (i.e. the first end) of the harness may have throwing weights mounted thereon.
2 5 The throw line, when releasably secured to the h~n~e~, is sufficiently long so as to extend across
the planar opening of the trailer to the ground on the side of the trailer when thrown thereover
from a first side of the trailer corresponding to the first longitudinal edge of the planar opening.
Furling means as provided for selectively rolling the flexible cover from the deployed position into
the storage position.
Advantageously the harness is non-resilient. The harness may include a pluralityof flexible straps, ropes or the like spaced apart in a plurality of "V"s along the second
longitudinal edge of the flexible cover.
In one aspect the furling means is an elongate member such as a pole mounted
along the second longitudinal edge of the flexible cover, releasably couplable by releasable
0 coupling means at one end thereof to a first end of an elongate crank, wherein the first end of the
elongate crank is flared such as conically flared to ass;st disentangled tie-downs which may
become wrapped around the elongate crank as the cranl~ is rotated to furl the flexible cover. In a
further aspect, the releasable coupling means is a universal joint coupling, preferably having a
resilient outer coating.
Brief Description of the Drawin~
Figure l is, in perspective view, a tractor and B-train incorporating the tarp roll
safety system of the present invent;on.
Figure 2 is, in perspective view, a trailer with the tarp cover rolled up.
Figure 3 is, in perspective view, a trailer w;th the tarp cover partly unrolled.
2 5 Figure 4 is, in perspective view, a trailer with the tarp cover completely unrolled.
Figure 5 is an enlarged partial view from Figure l.
~ 2 ~
Detailed Description of the Preferred Embodiment
Sawmills produce large quantities of wood chips. Conventionally, wood chips are
now transported from sawmills by tractor trailers such, as seen in Figure 1, where a conventional
tractor 10 pulls B-train chip vans or trailers 12, and in particular two such trailers aligned
longitudinally, one behind the other. Such chip trailers 12 are designed to carry large volumes of
wood chips 14 as may be seen in Figure 3.
Because of the large volume of wood chips that may be transported at one time,
0 the trailers are neces~rily also large, and it is therein that the problem arises, to which the present
invention is directed.
As will be readily understood, loads of wood chips in open trailers must be covered
during transport. Conventional wood chip trailers are basically open bins which may be filled
from above. The openings 16 of the bins are generally horizontal and planar and supported by
lateral cross-members 18. These trailers are typically equipped with tarpaulin covers 20. These
tarp covers 20 are typically stored by rolling in a lateral direction "A" across the top of the trailer
cross-members 18, so as to result in a longitudinally extending rolled tarp 20, such as seen in
Figure 2, extending the length of the trailer 12 along one side edge 22 of the trailer opening 16.
2 o To roll and unroll tarp 20, conventionally an operator has to either stand on a raised platform 24,
which conventionally may be folded down from a folded up storage position, so as to operate a
hand crank (not shown) connected to a longitudinally extending pole 26 shown as exposed end
26a in Figures 1-3 and 5, and better seen in Figure 4. Platform 24 would conventionally be
mounted so as to fold down in the space between front and rear trailers 12, rather than at the front
2 5 of the front trailer as sown in Figure 2 for illustration purposes. Pole 26 is attached to the free
edge 30 of tarp 20. Conventionally the operator may have to climb up onto wood chips 14 to
m~nll~lly assist the rolling and unrolling oftarp 20. These activities have proven to be hazardous,
especially in winter, where operators, who typically are on their own, slip and fall from the top of
trailers 12, thereby causing injury.
In the present invention rope harness 32 is used to assist unrolling tarp 20 so as to
cover a load of chips 14 without the need for the operator to climb up onto the trailer 12. For sake
of certainty, the two sides of the trailer will be referred to in reference to a trailer attached to a
truck where one side of the trailer would then correspond to the driver's side of the truck, and the
opposed side of the trailer would correspond to the passenger side of the truck. Thus, by
convention, although clearly not so as to be limiting, a rolled up tarp 20 is attached as seen in
o Figure 2 along the passenger side 22a corresponding to side edge 22 of the trailer opening 16.
The rolled up tarp 20 is free to be unfurled over the trailer opening 16, typically by
being unrolled over a load of wood chips 14 so that free end 30 of tarp 20 and pole 26 is draped
over the driver's side 23a, and in particular side edge 23, of the trailer opening 16.
Crar~ 28 may be releasably coupled to end 26a of pole 26, as better seen in
Figure S.
The two ends 32a and 32b of the V-shaped harness 32, are attached to pole 26 in
2 o the free edge 30 of the tarp 20. Harness 32 may have a short lead line extension 33 between the
vertex of the "V" and a weighted coupling 34. A throw line 35 releasably coupled to lead line 339
may be weighted at its free end by weight 36 to facilitate throwing of throw line 35 over opening
16 of the covered trailer 12. Weighted coupling 34 may be a threaded coupling or the like. With
the tarp 20 unfurled so as to cover over trailer open;ng 16, harness 32 is positioned over the top
2 5 surface of unfurled tarp 20 as seen on the rear trailer 12 in Figure 1, so that harness 32 lays flat
in its natural "V"-shape over tarp 20. To accomplish this, once tarp 20 is unfurled as described
below, weight 36, throw line 35 and lead line 33 is thrown over trailer 12 so as to lay harness 34
over tarp 20. The vertex of harness 32 or lead line 33 may then be secured to the side 22a of
trailer 12, and throw line 35 detached for storage.
Advantageously, lead line 33 is not so long as to drag on the ground, and weighted
coupling weighs approximately 4 ounces. Throw line 35 may be a 15 foot length of rope having
at its end a 12 ounce throw weight 36.
Tarp 20 may be rolled in direction A by use of a crank 28 releasably coupled to end
26a of pole 26, for example, by means of an elongate crank shaft 38 (shown shortened in Figure
0 5) releasably couplable to a universal joint coupling 40. Advantageously, crank shaft 38 is
sufficiently long so that the crank 28 may be turned from the ground. Further advantageously a
double offset crank handle 41 is mounted to the ground end of crank shaft 38 to assist in rotating
the shaft. As the tarp 20 is rolled, the harness 32 is rolled ;nto tarp 20, leaving lead line 33
h~nging from the rolled up tarp 20 on side 22a as seen in Figure 2.
Rolled up tarp 20 is held in place between uprights 50, which may be spring loaded
or otherwise resilient or somewhat flexible and ramp members 52, which may also be somewhat
non-rigid as, for example, of stiff rubberized material. Tarp 20 is furled up over ramp members
52 so as to drop into place between ramp members 52 and uprights 50. Ramp members 52 are of
2 o sufficiently low profile so that pulling on throw line 35 will urge rolled up tarp 20 over ramp
members 52, but rolled up tarp 20 will be held in place as trailers 12 are driven underneath
sawmill wood chip feed chutes.
With harness 32 thus rolled into the rolled up tarp 20 along edge 22, unrolling tarp
2 5 20 so as to cover a load of wood chips 14 becomes a simple matter ofthrowing throw line 35 and
lead line 33 in direction "B" over the top of a full trailer 12 where operator 8 has coupled throw
line 35 to lead line 33, taken weight 36 on the weighted end of throw line 35 and thrown it over
the top of the full trailer. In Figure 4, operator 8 has walked around to the driver's side 23a of
trailer 12, grasped throw line 35, and pulled on the line so as to draw harness 32 across the top of
the trailer that is, across opening 16 such as seen in Figure 3, at the same time thereby unfurling
tarp 20 over the load orwood chips 14. ~s tarp 20 is completing its unfurling, as sharp tug on
throw line 35 or lead line 33 by operator 8 causes tie down ropes 41 and bungy cords 41a to be
thrown from the top surface of tarp 20 so as to hang down side 23a of trailer 12 for ease of
retrieval. A hook or other elongate means may be employed to pull down tie down ropes and
bungy cords that remain lying on the top surface of tarp 20. With tarp 20 unfurled, tarp 20 may
be secured by tie down ropes 41 and bungy cords 41 a, to tie down hooks 42 along the lower sides
oftrailer 12.
Thus, in a first aspect, when it is desired to unroll the tarp from the uncovered
position to the covered position, the load covering method includes the use of a harness 32
attached to the free edge of a tarp in conjunction with a weighted line so as to cover a load of
wood chips without an operator having to climb onto the load. The methodology is illustrated in
1 5 sequence in Figures 2-4. In a second aspect of the methodology, it is important to note how tractor
10 is backed up so as to expose the front of the front trailer 12, thereby facilitating access by
operator 8 to the front edge of the corresponding tarp 20. Without such access, the operator could
not use crank 28 releasably coupled to coupling 40 mechanism to roll the tarp to the uncovered
positlon.
As set out above, elongate crank 28 cooperates with pole 26 in the free edge 30 of
tarp 20 by means of a universal joint coupling 40, so as to thereby assist in uncovering a load of
wood chips 14 contained in a trailer 12 having an opening 16. In a further aspect, the end 44 of
crank shaft 38 for releasable coupling with universal joint coupling 40 has a conically flared
2 5 surface 46, or otherwise a smooth three dimensionally enlarged end for assisting in de-t~ngling
lines 41 and bungy cords 41a which get wrapped around crank shaft 38 (as best seen in Figure S).
Universal joint coupling 40 may have an outer resilient coating or collar 48 such as neoprene or
the like, and end 44 may have a socket-like coupling 45 for releasable coupling with universal
joint coupling 40. Crank 28 may be secured for storage and transport against side 23a of trailer
12.
As will be apparent to those skilled in the art in the light of the foregoing
disclosure, many alterations and modifications are possible in the practice of this invention
without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to
be construed in accordance with the substance defined by the following claims.
