Note: Descriptions are shown in the official language in which they were submitted.
A ROLL-UP TARP APPARATVS
Backqround of the Invention
The present invention relates to a roll-up tarp
apparatus for open containers or the like. More
particularly, the present invention relates to a roll-up
tarp apparatus for an open truck box or trailer.
Roll-up tarp apparatus for truck and trailer bodies
having an open top are widely utilized in the trucking
and agricultural communities. For example, see U. S.
Patent Nos. 2,976,082, 4,234,224, 4,505,512, Re. 31,746,
etc.
US patent no. 2,976,082 to Dahlman utilizes a spindle
attached to one edge of a tarp with the other edge of
the tarp being attached to the truck box. The spindle ~ -
has a pair of spools attached at its ends and further
includes a hand crank at one end. A flexible cable is : ~-
stitched transversely of the tarp proximate its rear and
front edges. The flexible cables are attached to the ~`
spindle at one end and to vertically extending springs
on the other side of the truck box. The cables are used
to maintain contact between the top edges of the truck
box and the front and rear ends of the tarp. The spools
are also attached to the ends of a second set of cables, :
which cables in turn are connected at their free ends to ~ -
opposite ends of a horizontally extending coil spring ,~
mounted on the side of the truck box and resiliently
securing the cables together. These cables are wound
onto the spools as the tarp is unwound from the spindle ~
by turning the crank handle. The vertically and - -
horizontally extending springs cooperate to exert a -
tension on the tarp during rolling and unrolling of the
tarp. When in the covered position, the spindle is
suitably locked in place. In addition to other problems
Dahlman requires multiple sets of springs. These
springs require adjustment throughout their useful life. ~ ~
Corrosion and interference from dirt and other debris -
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can affect their performance. Additionally, the spindle
must be locked in the covered position. Also, there is
wear do to relative sliding of various parts caused by
action of the springs.
US patent no. 4,234,224 to Rosenvold utilizes a rod
attached to one edge of a tarp with the other edge being
attached to the truck box. The rod has a pair of spools
attached to its ends. A pair of ropes are attached to
the spools at one end and are attached at their other
end to a pair of springs mounted on the interior of the
truck box. The springs act to place the ropes and thu~
the rod under tension. A handle is attached to one end
of the rod for manually rotating the rod. As the tarp
15 is unrolled, the springs urge the tarp toward the -
covered position, thereby placing tension on the tarp
and acting to keep the tarp straight. In addition to
numerous other problems, as with Dahlman, the springs
ref~uire ad~ustment throughout their useful life. -
Moreover, they have a tendency to corrode which affects
their performance. Dirt and other debris can interfere
with their operation. Also, there is wear do to
relative sliding of various parts caused by action of
the springs. In addition, the front and rear edges of
the tarp do not tightly engage the top of the truck box
so as to prevent buffeting by the wind. Rosenvold
discloses various edge covers which might be used to
prevent the wind from traveling between the tarp and the
truck box top surface.
US patent no. Re. 31,746 discloses use of a roll bar
attached to one edge of a tarp with the other end of the -
tarp being attached proximate a top edge of the truck -
box. To retain the tarp in the covered state, a crank
handle is used to reverse roll the roll bar up under a
latch plate such that the tarp is wedged thereunder.
The crank handle must then be secured at the back end of --
the truck box to prevent the roll bar from unrolling.
In addition, to other numerous problems, the latching
process causes wear on the tarp. The user must be sure
to secure the free end of the crank handle when the tarp
S is in the covered po~ition, since release of the crank
handle will cause the tarp to be released from its
covered position. The crank handle must be retained on
the roll bar and stored at the back end of the truck box
which can interfere with operations at the back of the
10 truck box. If the load settles, the tarp may have a ~
tendency to become unlatched. -
US patent no. 4,505,512 discloses use of a roll bar
attached to one edge of a tarp by straps with the other -~
15 end of the tarp being attached proximate a top edge of ~- ~
the truck box. A crank handle is used to roll and -~-
unroll the tarp. To retain the tarp in the covered : -
state, the crank handle is used to reverse roll the roll ;~ -
bar into contact with hooks positioned along the side of -
the truck box and place the tarp under tension, and the
crank handle is then secured at the back end of the -
truck box to prevent the roll bar from unrolling.
Although, this design solves some of the above noted and ~
other problems associated with Re. 31,746, the crank - -~-
handle must still be secured in order to retain the
tension in the tarp and insure against inadvertent
uncovering of the truck box.
The present invention provides numerous improvements
over these and other roll-up tarp apparatus.
SummarY of the Invention --
The present in~ention additionally relates to a roll-up -~
tarp apparatus for an open container including a tarp
made of a flexible material. The roll-up tarp apparatus
includes means for fixedly securing a first side edge of
the tarp to a first longitudinal side of the truck box.
An elongated roll tube is attached to a second side edge
of the tarp. Crank means is interconnected to the
elongated roll tube for rolling the elongated roll tube
transversely of the open truck box, so as to cover the
truck box with the tarp or uncover the truck box with
the tarp. The elongated roll tube includes spool means
for winding and unwinding an elongated cable thereon.
The cable is interconnected at one end to the spool
means and proximate a second end to anchor means on a
second longitudinal side of the truck box, the spool
means being configured to wind cable onto the spool
means at the same rate that the tarp is unwound from the
roll tube. The anchor means placing the cable under
tension.
One advantage of an embodiment of the present invention
is that it is easy to use. No latching or locking steps
are necessary to retain the tarp in the covered
position. Upon being rolled into the covered state, the
roll-up tarp retains itself in the covered state without
any additional latching or locking steps.
Yet another advantage of one embodiment of the present -
invention is the use of an electric motor which allows
automatic operation of the roll-up tarp apparatus
without the user having to manually roll, unroll, or
secure the roll tube in the closed or open positions.
In one embodiment, the present invention can be operated
from the cab of a vehicle without the user having to
30 exit the cab. ~ ~
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Another advantage of an embodiment of the present
invention is that the tarp remains uniformly tight
during use regardless of whether it is in a fully opened
or partially opened state.
An advantage of yet another embodiment of the present
invention, reduces wear.
Still another advantage of one embodiment is that the
present invention does not require the use of any
springs which can corrode or whose performance can be
affected by continued use and which may require
adjustment during use.
Another advantage of an embodiment of the present
invention
provides a very tight seal between end edges of the tarp
and top edges of the truck box so as to resist buffeting
by the wind.
A further advantage of one embodiment of the present
invention is that no additional guides are required for
guiding the rolling and unrolling motion of the roll
tube/tarp arrangement. -
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An advantage of one embodiment of the present invention `
is that it provides a wire reinforced hose as the ;~
connector apparatus.
An advantage of yet another embodiment of the present
invention is that it provides an oblong spool and roll -~
tube combination which takes up less width along the
side of the truck when in the covered position.
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Yet another embodiment of the present invention provides
a roll tube have channels for receiving internal -
pro~ections of the spool.
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These an various other advantages and features of
novelty which characterized the invention, are pointed
out with particularity in the claims and next here to
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and forming a part hereof. However, for a better
understanding of the invention, its advantages and
objects obtained by its use, reference should be had to
the drawings which form a further part herein and to th~
accompanying descriptive matter, in which there is
illustrated and described a preferred embodiment of the
invention.
Brief Description of the Drawinqs
In the drawings in which like reference numerals and
letters indicate corresponding parts throughout the
several views,
Figure 1 is a view in perspective of an embodiment
of a roll-up tarp apparatus in accordance with the
principles of the present invention, the roll-up tarp
apparatus being illustrated mounted on the top of a
truck box and being disposed in a covered state;
Figure 2 is a partial, enlarged side elevational
view of the roll-up tarp apparatus shown in figure 1 in
the covered state, illustrating an electric motor being
mounted on the end of a roll tube for rolling the roll- -
up tarp apparatus back and forth between a covered and
an uncovered state;
Figure 3 is a partial, enlarged side elevational
view of the roll-up tarp apparatus shown in figure 1 in ~ ~ ;
the covered state, illustrating in more detail a
longitudinal edge of the r~ll-up tarp apparatus which is
interconnected to the roll tube.
Figure 4 is an enlarged, front end view of the roll-
up tarp apparatus shown in figure 1, illustrating a
mounting structure for pivotally mounting the electric
motor on the front end of the truck box, phantom lines
illustrating movement of the mounting structure upon
rolling of the roll-up tarp apparatus into the uncovered
state;
Figure 5 is a view similar to figure 4, illustrating
an alternate telescoping embodiment of the mounting
structure,
Figure 6 is an enlarged, partial perspective view
illustrating the roll-up tarp apparatus shown in figure
1 in an uncovered state, a longitudinal edge of the
roll-up tarp apparatus opposite the roll-tube being
attached to a top edge of the truck box;
Figure 7 is a diagrammatic, partially exploded end
view of the roll-up tarp apparatus in the uncovered
state as shown in figure 6,
Figure 8 is a an enlarged, side elevational view
illustrating an embodiment of an anchor apparatus which
anchors the roll-up tarp apparatus shown in figure 1 and
allows for adjustment of cable tension;
Figure 9A is a side elevational view of an alternate
embodiment of an anchor apparatus;
Figure 9B is a bottom view of the embodiment shown .~ ~.
in figure 9A;
Figure 10 is an enlarged side elevational view of :~
the tapered, spool positioned on the ends of the roll
tube of the roll-up tarp apparatus shown in figure 1; ;:- -
Figure 11 is a perspective view of an manually . :
operated alternate embodiment of a roll-up tarp
25 apparatus in accordance with the principles of the : . .
present invention illustrated on the top of a truck box; -~ :
Figure 12 is a partial perspective view of the roll- : :
up tarp apparatus shown in figure 11 with a crank :; .::: .:
apparatus removably attached to a roll tube of the roll~
30 up tarp apparatus; ~-
Figure 13 is a diagrammatic view illustrating two
different embodiments of connection apparatus which
might be used to interconnect the crank apparatus to the
spool; : :
Figure 14 is a diagrammatic view of an alternate
embodiment of a roll-up tarp apparatus in accordance
with the principles of the present invention which :
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includes two tarps and a third spool, the crank
apparatus being shown stored along a driver's side of
the truck box when the roll-up tarp apparatus is in a
covered state;
Figure 15 is a diagrammatic view similar to Figure
14 with the crank apparatus being stored along a
passenger's side of the truck box when the roll-up tarp
apparatus of figure 11 is in an uncovered state;
Figure 16 is a diagrammatic view similar to Figure
15 with the crank apparatus being stored at the back end
of the truck box when the roll-up tarp apparatus is in a
covered state;
Figure 17 is a diagrammatic view similar to figure
16 with the crank apparatus being stored at the front
end of the truck box when the roll-up tarp apparatus is
. in a covered state; ~ -.
Figure 18 is an alternate embodiment of a flexible
connector apparatus;
Figure 19 is a cross sectional view of an alternate
embodiment of a roll tube;
Figure 20 is an end view of an alternate embodiment
of a spool;
Figure 21 is a side elevational view of the spool
shown in figure 20; and
Figure 22 is a cross sectional view of the roll tube
of figure 19 inserted onto the spool of figure 20.
Detailed DescriPtion of the Preferred Embodiment
With reference now to the drawings, there is
30 illustrated in Figures 1 through 10, an embodiment of a ~-
roll-up tarp apparatus in accordance with the principles -
of the present invention, the roll-up tarp apparatus
being generally designated by the reference number 20.
It will be appreciated, that while the roll-up tarp
apparatus 20 is shown utilized with an open truck box or
semitrailer, the present invention has application to
other large containers having an open top requiring an
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easily and readily removable cover. The roll-up tarp
apparatus 20 includes a flexible cover or tarp 22 which
is stretched over and supported by a framework 24
suitably attached to the top of a truck box 26. The
tarp 22 is fixedly secured along a first longitudinal
side edge proximate a top edge 28 of a longitudinal side
of the truck box 26 which is on the passenger side of
the vehicle in the embodiment shown. An opposite,
second longitudinal edge of the tarp 22 is attached to a ~ -
hollow roll tube 30. In the embodiment shown, there is
a tapered spool 34 fixedly mounted to each end of the
roll tube 30. Each of the tapered spools 34 is
interconnected by a cable 38 to an anchor 40 suitably
mounted on a side 42 of the truck box 26 which is on the
driver's side of the vehicle. The anchors 40 are
adjustable to place the cables 38 under a desired -;~
tension. Since the tarp 22 is attached to the roll tube
30, the tarp 22 is similarly placed under tension. The
spools 34 are tapered so that the cables 38 are rolled
onto and unrolled from the spools 34 at the same rate
that the tarp 22 is unrolled from and rolled onto the
roll tube 30. Accordingly, once the cables 38 and tarp
22 are placed under tension by adjusting the anchors 40,
that tension is maintained throughout the rolling and
unrolling proces~ such that roll-up tarp apparatus is
maintained under the same tension during operation.
An electric motor 44 is shown mechanically connected to
the spool 34 at a front end 45 of the truck box 26, a
pivoting support structure 46 pivotally supporting the
electric motor 44. The pivoting support structure 46 is
pivotally attached to the front end 45 at 47 and is
fixedly attached to the motor 44 so as to prevent the
motor housing from rotating when the motor 44 is
switched on and yet allow the motor 44 to travel with
the roll tube 30 as it moves across the opening of the
truck box 26. In the embodiment shown, the motor 44 is
a twelve (12) volt motor and is suitably electrically
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connected by electrical wires 48 to the vehicle's
electrical wiring system/battery so as to derive
electrical power for its operation. An electrical
switch (not shown) is preferably mounted in a cab 27 of
the vehicle and/or on the side of the truck box 26
itself, for switching the motor 44 on or off.
A preferred embodiment of the switch might include an
off position, a forward roll position and a reverse roll
position for rolling the roll tube 30 in a clockwise or
counter clockwise direction and thus cover or uncover
the truck box 26 with the roll-up tarp apparatus 20.
The switch might be biased to the off position such that
upon releasing the switch, the switch returns to the off
15 position and switches off the motor 44. The switch -
might also include circuit breaker circuitry such that
when the roll tube 30 reaches the fully covered position
or fully opened position, the motor 44 is switched off
automatically.
The embodiment shown in figures 1 through 10 will now be
discussed in more detail. The framework 24 supporting
the tarp 22 over the truck box opening includes end caps
50 at the front and back ends of the truck box 26 and
spaced apart curved bows 52 intermediate of the end caps
50 and extending between the top side edges of the truck -
box 26. It will be appreciated that the framework 24
might take on any number of configurations. As
illustrated in Figure 2, the end caps 50 preferably
include a ridge 51 which assists in forming a tight seal
between the surface of the end caps 50 and the tarp 22.
Referring now to figures 2 and 3, the longitudinal edge
of the tarp 22 interconnected to the hollow roll tube 30
is sihown in more detail. As illustrated in figure 3,
the tarp 22 is attached along its second longitudinal
edge to the roll tube 30 by inserting the roll tube 30
into a hem 60 along the edge of the tarp 22. A second,
smaller hem 62 is located on a wall of the hem 60 for
receipt of an elongated flat member 64 which is inserted
into the hem 62. The tarp 22 is secured to the roll
tube 30 by riveting or otherwise suitably securing the
elongated member 64 by fasteners 66 to the roll tube 30
thereby preventing the roll tube 30 from rotating within
the hem 60. It will be appreciated that the tarp 22
might be attached to the roll tube in numerous ways and
be in keeping with the principles of the present
invention. For example, as opposed to being directly
attached to the tarp 22, the roll tube 30 might be
removed from the tarp 22 and be interconnected to the
tarp by straps.
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The roll tube 30 has a relatively large diameter whichmay vary depending on the length of the truck. The
diameter is relatively large so as to reduce the number ~ ;
of turns required to unroll or roll-up the tarp. For
example, a typical outside diameter of the hollow roll --
tube 30 might be from three and one-half inches (3 1/2)
to four (4) inches such that only nine to ten turns of ~
the roll tube 30 are required to completely cover or ; :
25 uncover the truck box 26. A typical wall thickness ;~
might be one-sixteenth (1/16) inch. The roll tube 30 is
designed to have a relatively heavy weight, e.g., a
twenty (20) foot length of roll tube 30 with an outside
diameter of three and one-half (3 1/2 inches) might -
30 weigh roughly fifty (50) pounds. The roll tube 30 might ,
be made of any number of materials; e.g., zinc plated
steel. -
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As illustrated in figures 2 and 3, a drive shaft 43 of
the motor 44 is suitably, fixedly attached to an end of
the spool 34 such that upon rotation of the drive shaft ; -
43 by the motor 44, the roll tube 30 is made to rotate.
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The pivoting support structure 46 is suitably, fixedly
attached to the motor housing such that the entire motor
doe~ not rotate upon rotation of the drive shaft 43.
Thi~ might be accomplished by any number of well known
methods. In the embodiment shown, the pivoting support
structure 46 is suitably attached to a flat surface of a
cradle structure 49 of the motor housing having a curved
surface for receiving the curved surface of the motor
44. The cradle structure 49 or equivalent housing
structure is suitably secured to the motor 44 and is
typically included with the motor 44 as a part of the
motor~s housing by the motor's manufacturer. The drive
shaft 43 is preferably removably connected to the spool
34 such that the motor 44 can be mechanically
disconnected from the roll tube 30 if desired. This
might be accomplished by any number of well known
methods; e.g., by telescopingly connecting the drive
shaft 43 to a projection (not shown) extending out from
the end of the spool, with a lock pin 41 or the like
20 interconnecting the drive shaft 43 to the projection. -
This will enable ready replacement of the motor 44 or
mechanical operation of the roll-up tarp apparatus 20,
should the motor be removed, by use of a suitable crank
handle configured to attach to the pro~ection of the
spool 34 or by attaching a crank handle to an adaptor on
the spool 34 at the back end of the truck box 26. The --~
force required to rotate the roll tube 30 will vary
depending on where the roll tube 30 is located during
the rolling/unrolling process, the force required is ~;
less than most conventional roll-up tarp designs. In
the present invention, the greatest force is required
when the roll tube 30 is positioned in the covered state
along the side of the truck box 26 since the weight of
the roll tube 30 must be overcome to roll the roll tube
30 up the side wall of the truck box 26.
Various sizes and configurations of electric motors will
work with the present invention. For example, a one
horsepower motor with a 100 to 1 ratio or a 2 horsepower
motor with a 50 to 1 ratio might be used. The gear
reduction provides the motor with an added internal
resistance to rotation of its drive shaft when the motor
is switched off. Accordingly, when switched off, the
motor and pivoting support structure 46 will prevent
rotation of the roll tube 30 regardless of where the
roll tube 30 is when the motor is switched off.
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Illustrated in figures 4 and 5 are two embodiments of
the pivoting support structure 46. Both embodiments are
illustrated as being pivotally mounted at location 47 at ~
15 the front end 45 of the truck box 26. The embodiment ~ -
shown in Figure 4 includes two elongated members 54a,b ~ -~
pivotally interconnected to one another at location 53
so as to allow the pivoting support structure 46 to .
follow the movement of the roll tube 30 across the top ;
of the truck box 26. Various positions of the pivoting
support structure 46 are illustrated in phantom line. ~`
If the motor 44 should fail, the members 54a,b can be -
disconnected at location 53 and the member 54b used as a
crank handle to manually rotate the motor 44 so as to
roll and unroll the tarp 22. The embodiment illustrated
in Figure 5, includes two telescoping members 56a,b. In ~ -~
both embodiments, the electrical wires 48 are connected ;
to the pivoting support structure 46 by a plurality of
epaced apart wiring harnesses 58 and might be
interconnected to short lead wires from the electrical
motor 44 by an adaptor allowing easy connection and
disconnection. It will be appreciated that numerous
other embodiments of the pivoting support structure
might be utilized in keeping with the principles of the
invention. For example, a pliable, resilient fiber
glass rod might be pivotally mounted at location 47.
The fiber glass rod would have a length greater than the
14
distance between the location 47 and the top of the
truck box 26. The fiberglass could be interconnected to
the motor in a bowed condition. Because of its length,
the fiberglass would remain bowed to varying degrees
during its travel with the motor across the truck box.
As illustrated in figure 6, the tarp 22 is fixedly
secured along a longitudinal edge thereof to the top
edge 28 of the truck box 26 on the passenger side of the
vehicle. In the embodiment shown, an elongated member
57 is positioned in a hem portion 58 along the edge of
the tarp 22. Suitable fasteners 59 are used to attach -
the elongated member 57 proximate a top edge of the
truck box 26 so that the longitudinal edge of the tarp ~ -
22 is correspondingly secured proximate the top edge of
the truck box 26. As illustrated in figure 7, the
cables 38 have a length such that the roll tube 30 is
prevented from rolling over the top edge of the truck
box 26 when in the fully uncovered position. However,
if desired, the length of the cables 38 can be such as
to allow the roll tube 30 to roll over the top edge of
the truck box 26. It will be appreciated that other
suitable apparatus for securing the tarp 22 along its
first longitudinal edge to the top edge 28 of the truck
box 26 might be utilized in keeping with the principles
of the present invention.
Illustrated in figure 8 is an embodiment of the anchors
40 in accordance with the principles of the present
invention. The anchors 40 are mounted on the side 42 of
the truck box so as to be roughly in alignment with an
end groove of the narrow diameter end of the spools 34
where the cable 38 comes off the spool 34. The anchors
40 shown include an L-shaped plate 70 suitably attached
to the side 42 of the truck box 26 by suitable fasteners
72 projecting through rectangular openings which allow
for some horizontal adjustment of the anchor. A
threaded eye bolt 74 is freely, slidably received in an
aperture of a horizontally extending portion 76 of the
plate 70. The cable 38, which might have a diameter of
one quarter (1/4) inch, is received in an eyelet 78 of
the eye bolt 74 and is suitably clamped by a clamp 80 so
as to secure the cable 38 to the anchor 40. The eyebolt
includes cooperating locking nuts 82 for locking the
eyebolt 74 in place. However, the top locking nut 82
can be loosened to enable vertical adjustment of the
eyebolt 74 by threadably adjusting the bottom locking
nut 82 relative to the eyebolt. Once the eyebolt 74 is
suitably positioned, the top locking nut 82 is
threadedly tightened. Accordingly, the eyebolt 74 can - -
be vertically adjusted to adjust the tension of the -
15 cables 38 which are relatively inelastic. ~ -
The adjustable nature of the anchors 40 allows for
adjustment of the cable tension, and thus tarp tension,
as desired at the time of installation. The anchors 40
are preferably mounted high up on the side of the truck
box 26 so that they can not be readily reached from the
ground so as to make them less susceptible to tampering.
Moreover, it is anticipated, that once the tension of
the cables 38 is ad~usted at installation, there will be
very little need for further adjustment of the anchors
40 if at all. Since the anchors 40 anchor the end of
the cables 38 and the other end of the cables are -~
attached to the roll tube 30, the cables 38 do not slide
relative to the end caps 50, thereby significantly
reducing wear of the cables 38.
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Illustrated in figures 9A,B, is an alternate embodimen$ :
of the anchors 40 which includes a bracket 92 having
rectangular openings 99 for receipt of a threaded faster -
(not shown) to enable the bracket 92 to be fastened to
the side of the truck box 26. The rectangular openings
99 allowing some horizontal adjustment of the bracket
. .
92. Mountad on the bracket 92 is a ratchet arr~ngement
includlng a ratchet whe~l 93 and a pawl 94. The ratchet
wheel 9~ incl~ s a hex nut end 95 which can be - -
operated by a wrench. The cable 33 is at~ached -to a
cylinder 96 of the ratchet wheel '33 by being threaded
through two apertures ~7jg~. It will be-appreciated
that numeLous other embodiments of anchor~. might be used
in keeping with th~3 principles of the invention.
ln Referring now to figure 10, an embGdj.meTIt of the spools
34 which are suitably, fixedly attached at: opposite ends
of ~he roll tuLle 30 is illustrated. The spools 34 might
be attached to the roll tube 30 in any number of
different ways. In the preerred embodiment the spools
34 are nlade from machined aluminum or aluminum casting
to minimi~e their weight. The spools 34 might also be
made of injection molded plastic so as to keep their
weight to a minimum. In the embodiment ~hown, the
spools are l~lade as a one piece item. The spools 34 are
tapered and inslude a spiralling groove 88 having a
number oP turns and configured for receipt of the cable
38. The taper of the spools 34 is predetermined such
that the rolling/unrolling of the cable 38 onto the
spool6 34 occurs at thé same rate as the
25 rollin~!unrolling of the tarp 22 onto the hollow roll -
tube 30. Accordingly, once the cables 38 have been
attached to the anchors 40 and adjustably tightened, the
cables 38 and the tarp 22 will remain in uniform tension
as ~he tarp 22 is rol'ed onto and unrolled from-the roll
tube 30. Thus wheth~r in a fulLy unco~ered position, a
fhlly covered po~ition, or a partially covered position,
the cables 38 and the tarp 22 will remain under the same
tension.
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When viewed from the front o the -trucX box 26 as shown
in figure 1, the tarp 22 is wound onto the roll tube 30
whe~ uncovering the truck box 26 by rolling the roll
17
tube 30 in a counter clockwise direction, and the tarp
22 is unwound from the roll tube 30 when covering the
truck box 26 by rolling the roll tube 30 in a clockwise :
direction. When positioned along the side 42 of the
truck box 26, the cables 38 extend up from the anchors
40 between the side 42 of the truck box 26 and the
spools 34 and then onto the spools 34. The number of
turns of the spiral groove 8~ on spools 34 is preferably
equal to the number of turns required to completely -
unroll or roll the tarp 22 across the truck box 26.
Specific dimensions of one embodiment of the spool will
now be provided by way of example; however, it will be
appreciated that this information is provided for
illustrative purposes and is not intended to limit the
invention to the dimensions provided. The specific
dimensions will vary depending on any number of ~ ~
parameters such as tarp thickness, size of roll tube, ~-
width of truck box, etc. The spool 34 includes a rim
portion 90 which is slightly larger, 3.74 inches in this
embodiment, than the outside diameter of the roll tube
30, and a cylindrical portion 91 having an outside
diameter, 3.42 inches in this embodiment, which is sized
to fit inside the roll tube 30 so as to facilitate
25 insertion of the cylinder portion 91 into the roll tube -
30. The rim portion 90 acts as a stop to limit the
distance the spool 34 is inserted in the roll tube 30.
The roll tube 30 can then be riveted or otherwise
secured to the cylinder portion 91. The rim portion 90
30 also functions to prevent the cables 38 from -
inadvertently slipping over the spool 34 and onto the ~ -
roll tube 30. At the distal, wide diameter end of the
spool 34, the outside diameter is 4.580 inches. The
spool 34 shown has a thicker wall structure than the
roll tube 30, the spool having an inside diameter of 2.5
inches. The taper of the spool shown is roughly six to
seven degrees. The longitudinal length of the spool 34 ;
18
is 3.475 inches. The grooves have a width of one
quarter inch so as to receive quarter inch diameter
cable and a depth of .20 inches. Groove edges are
radiussed to reduce wear on the cables 38. By way of
example, in a roll-up tarp apparatus 20 using eighteen
ounce vinyl coated nylon or polyester tarp, the
cable/tarp winding per turn of the roll tube 30 is as
follows starting at the narrow end of the spool:
Turn Cable/Tarp Nound
l 10.99 inches
2 11.24 inches
3 11.49 inches
4 11.74 inches
11.99 inches
6 12.~4 inches
7 12.49 inches
8 12.74 inches ..
9 12.99 inches
~ :
.
In the embodiment illustrated in figure lO, the cable 38 ~ :
is interconnected to the spool 34 by inserting an end o~
the cable 38 through an aperture 86 in a groove 88a
proximate a distal end of the spool 34. By adjusting
the location of the aperture, the roll-up tarp apparatus ~
20 can be adjusted for use for differing thicknesses of :
tarp. As illustrated in figures 6 and 7, a suitable :.
clamp 89 is clamped onto the end of the cable 38 on the :~
inside of the spool 34 so as to prevent the cable 38
from slipping back out of the aperture 86, thereby .
retaining the end of the cable 38 on the inside of the
spool 34. It will be appreciated that the cable 38 :~
might be interconnected in any number of ways to the
spool 34 and yet be in keeping with the principles of
the invention. As illustrate in figure 10, the vinyl -~
coated cable 38 preferably has a diameter larger than
the depth of the grooves 88 such that when rolling over :~
the end caps 50 the spools 34 rest on the vinyl coated -~
cables 38 such that the vinyl coated surface of the
cables 38 engages the surface of the end caps 50 and the
'. .:; ' ":~ . '
19 ' ,,
spools 34 do not engage the surface of the end caps 50. ~ -
In a preferred embodiment, the depth of the outer most
groove 88a is less deep than the other grooves and is
less than the diameter of the cables 38. The other
grooves 88 are deeper to assure that the cable will
properly wind and unwind from the grooves 88. For
example, if using one quarter inch cable, the outermost
cable receiving groove 88a might be roughly .180 inches
deep, while the other grooves might be .200 inches or ~ ~-
more in depth. It will be appreciated that the front
and back spools will be mirror images of one another.
Illustrated in figures 11 through 17 are manually
operated embodiments of a roll-up tarp apparatus lO0.
(Features in figures 11 through 17 corresponding to like
features in figures 1-10 have the same reference ~-
numerals.) In the manually operated embodiments, as ~ -
opposed to use of an electric motor 44l the roll tube 30
is made to roll by use of a manually operated crank
apparatus 102. In the embodiment shown, the crank
apparatus 102 includes a crank handle 101 and an
elongated crank handle extension 103 suitably secured to
the crank handle 101, which enables the operator to
manually roll the tarp 22 while standing on the ground.
Preferably the crank handle 101 is removably connected
to the crank handle extension 103 to enable removal -
therefrom. The crank handle extension 103 might be
telescoping so as to enable adjustment of the length of
the crank apparatus 102. This is particularly useful on ;
truck boxes 26 which have adjustable side extenders for
raising and lowering the height of the sides of the
vehicle. ;
'
Further, in th0 embodiment shown, the crank apparatus
102 is preferably removably connected to the roll tube
30 such that the crank apparatus 102 can be removed at
any time if so desired, including when the tarp 22 is in
.
the covered state as is illustrated in figure 11. ~s
further illustrated, in the embodiments shown, the crank
apparatus 102 is connected to the spool 34 proximate the
back end of the truck box 26 so as to allow operation at
5 the back end of the truck box 26; however, the crank
apparatus 102 might also be connected to the spool 34 at
the front end of the truck box 26, if so desired.
As illustrated, the crank apparatus 102 is
10 interconnected to the spool 34 at the back end of the
truck box 26 by a connector apparatus 104. More
particularly, illustrated in more detail in figure 12
are two embodiments of such a connector apparatus 104.
A first embodiment, which is shown in figures 11 and 13
15 through 15 as well, includes a flexible connector, in
A particular, a coil spring 106 attached at a first end to
the crank handle extension 103 and at an opposite end to -
the spool 34. In the embodiment shown, an end of the
crank handle extension 103 is slid into the coil spring
106 and is welded to the coil spring 106. Other types
of flexible connectors might be used such as a flexible
woven cable or a flexible hose. The flexible connector
allows operation and storage of the crank apparatus 102
at various angles relative to the end of the roll tube
30. In particular, the coil spring 106 allows a much
greater range of operating angles than a conventional u~
~oint; for example, the crank apparatus 102 with the
coil spring 106 can be operated at an angle up to 90
degrees relative to the roll tube 30. This allows -~
operation of the crank apparatus 102 in locations where
there is very little room or clearance to operate; e.g., -~
at the front end of the vehicle. Moreover, if the crank ;
apparatus 102 is attached to the back end of the
vehicle, the coil spring 106 allows the user to stand at
35 the side of the vehicle well clear of the back end. ~`
The coil spring 106 may have various configurations and
sizes and yet be in keeping with the principles of the
present invention. For example, a "pull typen coil
spring six to eight inches in length and with an outside
diameter of two inches and an inside diameter of one and
one-half inches might be used. A ~pull type~ spring is -
one wherein the coils are close together as opposed to a
~push type~' coil spring wherein the coils are farther
apart.
A second embodiment of the connector apparatus 104,
includes a conventional u-joint 108 having two,
interacting parts 110 and 112. The u-joint 108 might be
interconnected in any number way to the crank handle
extension 103; e. g., welding the part 112 to an
extension adaptor 105 which in turn is received in the
crank handle extension 103 and suitably secured thereto;
e.g., a bolt or pin might be inserted through the
extension adaptor 105 and the crank handle extension 103
so as to removably retain the two parts together.
Should the crank handle extension 103 be damaged, it can
preferably be released from the extension adaptor 105 by
removal of the bolt or other fastener which might be
used, so as to enable replacement of the crank extension
103.
Both the coil spring 106 and the u-joint 108 in the
embodiments shown in figure 12 are removably
interconnected to the spool 34 at the end of the roll
tube 30. In the embodiments shown, this is accomplished
by suitably, fixedly attaching a projection 114,116 to
the coil spring 106 and u-joint 108, respectively. This
might be accomplished in the case of the coil spring 106
by inserting the projection 114 into the coil spring 106
and welding the parts together, and in the case of the
u-joint 108, by welding the projection 116 onto the end
of the component part 110. The projections 114,116 are
sized and configured to receive ia rectangular projection
35 fixedly attached to the spool 34. The projections -
114,116 include an aperture 120,122 respectively, sized
and configured to align with an aperture 36 in the
projection 35 of the spool 34 such that upon insertion
of one of the projections 114,116 onto the projection 35
and alignment of the apertures, a lock pin 126 can be ~-
inserted through the apertures to removably attach the
connector apparatus 104 and its corresponding crank
apparatus 102 to the spool 34 of the roll tube 30. A
safety pin 128 is preferably used to retain the lock pin
126 in place. It will be appreciated that the connector -
apparatus 104 might take on any number of configurations
and be interconnected in any number of ways to the spool
34 and the crank apparatus 102 and still be in keeping
with the principles of the present invention.
:, ~ .:
As illustrated in figures 14 through 17 the crank
apparatus 102 can be stored in any number of positions.
As illustrated in figures 14, 16 and 17, the crank
apparatus 102 might be stored along the driver~s side 42
of the vehicle or at the back or front end when in a
covered state. In figures 14 through 17, a free end of --~
the crank apparatus 102 is placed in a bracket 107 on
the truck box 26. Preferably the crank apparatus 102 is
stored at a slight angle relative to the vertical to
assure that the crank handle 101 does not hang below the
bottom of the truck box 26 so that it is not damaged by
debris, etc. while driving the vehicle. Preferably the
crank apparatus 102 is stored along the side of the
vehicle so as to not interfere with the back end of the
vehicle. Of course, the crank handle 102 might also be ~
removed from the roll tube 30 and stored elsewhere. If ~- -
the back end of the roll tube 30 is not readily `
accessible, the crank apparatus 102, particularly if the
coil spring 106 is being used, might be interconnected ;~
to the spool 34 at the front end of the vehicle and
23
stored at the front end of the trailer as illustrated in
figure 16. When in the uncovered state, the crank
handle 102 might be stored on the passenger's side of
the vehicle as shown in Figure 15.
As illustrated in figure 14, multiple roll tubes 30a,b
might be interconnected by a tapered spool 34a so as to
provide additional anchors 40, if desired, when using
the roll-up tarp apparatus 20,100 on semi-trailers or
the like having an extended truck box length. As
illustrated in figure 14, an end cap like structure 50a
would provide a support surface for the spool 34a to
roll on and provide support for inner ends of two
separate tarps 22a,b attached to the roll tubes 30a,b.
The structure 50a will preferably include two spaced
apart, parallel ridges (not shown) extending
transversely of the truck box 26, similar to the ridge
51 on the end caps 50, so as to facilitate provision of
a tight seal between the structure 50a and the inner ~ ;
ends of the tarps 22a,b. It will be appreciated that
the spool 34a will have a taper similar to the spools 34 ~-
so as to facilitate maintaining a uniform tension in the
tarps 22a,b as they are rolled and unrolled. The spool
34a might be suitably mounted on the ends to the roll
tubes 30a,b in any number of ways such as by welding or
the like.
The roll-up tarp apparatus 20 is mounted on a truck box
26 by fixedly securing one longitudinal edge of the tarp :
22 proximate the top edge 28 of the truck box 26 on the
passenger~s side of the vehicle. It will be appreciated
that the tarp might be fixedly secured to either side
top edge or end top edge. For example, on a gravel
truck, the tarp 22 might be fixedly secured to the front
end top edge. The opposite longitudinal edge of the
tarp 22 has the roll tube 30 inserted into the hem 60.
The spools 34 are preferably fixedly secured to the ends
24
of the roll tube 30 before insertion into the hem.
Cables 38 are then attached to the spools 34. The tarp
22 is unrolled into the covered position and the length
of the cables 38 is adjusted so as to terminate properly
with the anchors 40 which were preferably previously
mounted to the drivers side of the vehicle. The pivotal
support structure 46 is suitably mounted to the front
end side of the vehicle or any other side depending on
the orientation and location of the roll tube 30. The
10 motor 44 is mounted on the pivotal support structure 46~ ~ -
and onto the spool 34 proximate the front end of the
truck box 26. The motor 44 is electrically wired to the~ ;
vehicle~s wiring system or battery. Of course before
attaching the tarp 22 to the truck box, the support
framework 24 is typically installed.
In use, the user will simply switch on the electric
motor to clockwise or counterclockwise roll the roll
tube 30 as desired. No latching, locking, etc. is
necessary. The roll-up tarp will remain in the covered
position or in any other position where the roll tube is
stopped including fully opened and partially opened `~
positions. In addition, in the automatic version of the
invention illustrated in figures 1-10, there are no
crank handles to worry about. With the automatic
version of the invention, the operator while in the cab
and driving the vehicle can open and close the roll-up
tarp apparatus. In the manual version, the operator
~imply rolls and unrolls the tarp 22 with the crank
30 apparatus 102 and stores the crank handle wherever -~
desired. The operator can remove the crank handle 102
and store it in an out of the way place. With the
present invention, wherever the roll tube 30 is stopped, ~ `~
the tarp 22 will be under tension. Moreover, the
tension is the same regardless of where the roll tube 30
stops.
r~ - ~
i
Illustrated in Figure 18 is an alternate embodiment of
connector apparatus 104' which included a wire
reinforced hose 150 which provides for a flexible
connector. The hose 150 shown has two wire reinforced
hose layers 151 so as to be two ply. It will be
appreciated that there might might be varying numbers of
layers of wire reinforced hose. A coil spring 152 is
disposed inside the hose 150 to prevent the hose 150
from collapsing. The hose 150 shown has little or no
resilient memory. Disposed at the ends of the hose 150
are fittings 154 and 156 having threaded portions 155
and 157 respectively. Threadedly attached to the
fitting 154 is a hollow cylindrical extension 158
configured to slide onto the end of the crank extension
15 103. The extension 158 includes an aperture 160 for
receiving a bolt or the like so that the connector
apparatus 104' can be attached to the crank extension
103. Fitting 156 is attached to an extension 162
including a plate portion 164 which in turn is attached
20 fasteners 168 to a plate portion 166 on the end of the ~
spool 34'. -
Illustrated in Figure 19 is an alternate embodiment of a
roll tube 30'. The roll tube 30' shown has an oblong
configuration. The embodiment shown has a dimension of
roughly two (2) inches by four and two tenths inches -~
(4.2). The roll tube 30' is used in conjunction with an -~
oblong spool 34' having a similar oblong configuration
as shown in figures 20 and 21. The embodiment shown has
a dimension of roughly three and two tenths inches (3.2)
by five and two tenths (5.2) inches. Figure 22
illustrates the spool 34' inserted onto the end of the
roll tube 30'. The roll tube 30' includes four channels
170 which receive internal projections 172 of the spool
34' and serve to prevent relative movement between the
roll tube 30' and the spool 34'. Once inserted onto the
end of the roll tube 30', the spool 34' is then suitably
;.~,? ~
.
26
fastened to the roll tube 30~ by fasteners and/or ~ ~ -
welding. One of the channels 170 also serves to ~- -
received a hem portion 174 of the flexible cover 22 so ~
as to fasten the cover 22 to the roll tube 30. The ---
flexible cover 22 is wrapped around the roll tube 30
and fastened at location 176. In this embodiment the
roll tube 30l might be aluminum and the cover 22 a
polyester material. It will be appreciated that in this
embodiment an interior surface 178 of the spool 34' is
slightly tapered in a fashion similar to the exterior.
However, as shown, the projections 172 maintain a
uniform inside dimension.
The above embodiment provides several advantages. The ~
oblong roll tube 30' and spool 134' ~'walk~ over a heap - -
load in the truck during the covering process. When the ~
truck is covered, the roll tube 30' hangs on the side of ~ ;
the truck with its narrow dimension facing sideways and
away from the truck. This reduces the overall width of ~-
the truck and its accessories and improves its looks.
In addition, the spool 34~ is more easily assembled onto
the end of the roll tube 30'.
It is to be understood, that even though numerous
characteristics and advantages of the invention have
been set forth in the foregoing description, together
with details of the structure and function of the
invention, the disclosure is illustrative only, and
changes may be made in detail, especially in matters of
shape, size, and arrangement of the parts within the
principles of the invention to the full extent indicated
by the broad general meaning of the terms in which the
appended claims are expressed.
. : ',' ' ~ ' .
,'~;'.~ " '. ' .
