U.S. patent application number 09/812294 was filed with the patent office on 2001-10-04 for hold-down locking mechanism for a flexible cover system.
This patent application is currently assigned to Aero Industries, Inc.. Invention is credited to Henning, Steven A..
Application Number | 20010026076 09/812294 |
Document ID | / |
Family ID | 24123990 |
Filed Date | 2001-10-04 |
United States Patent
Application |
20010026076 |
Kind Code |
A1 |
Henning, Steven A. |
October 4, 2001 |
Hold-down locking mechanism for a flexible cover system
Abstract
A wind-actuated hold-down mechanism is provided for restricting
movement of a deployment component of a flexible cover deployment
system associated with an open-topped container. In certain
embodiments, the mechanism includes a vane member pivotably mounted
to either the container or the deployment component. The vane
member can include one locking element that engages another locking
element mounted on the other of the container or the deployment
component. The hold-down locking mechanism in certain embodiments
is configured to restrict movement of a bail member for a cover
deployment system. Other embodiments are configured to engage the
end of a transverse bow. A hold-down mechanism can be biased to a
neutral position clear of engagement between the container and the
deployment component, using either a mechanical biasing component
or a gravity biasing feature.
Inventors: |
Henning, Steven A.;
(Speedway, IN) |
Correspondence
Address: |
Michael D. Beck
Baker & Daniels
300 North Meridian Street, Suite 2700
Indianapolis
IN
46204
US
|
Assignee: |
Aero Industries, Inc.
|
Family ID: |
24123990 |
Appl. No.: |
09/812294 |
Filed: |
March 20, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09812294 |
Mar 20, 2001 |
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09532987 |
Mar 22, 2000 |
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6234562 |
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Current U.S.
Class: |
296/100.16 |
Current CPC
Class: |
B60J 7/185 20130101;
B60J 7/085 20130101 |
Class at
Publication: |
296/100.16 |
International
Class: |
B60P 007/02 |
Claims
What is claimed is:
1. A hold-down locking mechanism for a cover system for an
open-topped container, the cover system including a flexible cover
deployable over the container by a deployment system, the
deployment system having a moving deployment component connected
between the container and the flexible cover, said mechanism
comprising: a stop member attached to one of the container or the
moving deployment component; and a locking member pivotably mounted
on the other of the container or the moving deployment component,
said locking member including a locking element configured to
engage said stop member to restrict relative movement between said
locking member and said stop member.
2. A hold-down locking mechanism for a cover system for an
open-topped container, the cover system including a flexible cover
deployable over the container by a deployment system, the
deployment system having a moving deployment component connected
between the container and the flexible cover, said mechanism
comprising a wind-actuated locking member disposed between the
container and the moving deployment component, said locking member
configured to restrict relative movement between the moving
deployment component and the container when said locking
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to flexible covers or tarping
systems for open-topped containers. The invention most particularly
concerns an apparatus adapted for use with an open-topped container
bed on a land vehicle, such as a dump truck. More specifically, the
invention pertains to a mechanism for restraining the flexible
cover or tarp when the vehicle is moving.
[0002] Many hauling vehicles, such as dump trucks, include
open-topped containers used for hauling or storing various
materials. In a typical dump truck application, the dump body is
used to haul a variety of particulate material , such as gravel and
the like, as well as organic materials, such as grain or
produce.
[0003] Depending upon the nature of the materials stored in the
open-topped container, it is often desirable to provide a cover for
the container. A cover is particularly valuable when the containers
are part of a vehicle, such as a dump truck. Rigid covers are well
known that may be hinged from one end of the container body and
pivoted from an open to a closed position. While rigid covers may
be acceptable for stationary containers, the same is usually not
true for land vehicles. In this industry, the rigid covers have
given way to flexible cover systems. Systems of this type utilize a
flexible tarpaulin that can be drawn from a stowed position at one
end of the container, to a deployed position covering the open top
of the vehicle container or bed. The flexible cover or tarpaulin is
preferable in this arena because it can be easily stowed when the
cover is not necessary, such as when a dump truck is being loaded.
In addition, the flexible cover is generally easier to deploy than
a rigid cover.
[0004] A variety of flexible cover or tarping systems have been
developed that are geared toward particular hauling vehicle
applications. One such tarping system is the Easy Pull.RTM. System
of Aero Industries, Inc. The Easy Paul.RTM. System includes a
flexible tarp that is wound around a spool at one end of the
container body. A rope attached to the free end of the tarp can be
used to unwind the tarp from the roller and draw the tarp along the
length of the vehicle container bed.
[0005] Another cover system particularly suited for open-topped
containers on hauling vehicles, is the Easy Cover.RTM. Tarping
System also of Aero Industries, Inc. The Easy Cover.RTM. Tarping
System includes a U-shaped bail that is pivotably mounted to the
base of the vehicle container body. The horizontal section of the
U-shaped bail is attached to the tarp, while the free ends of the
vertical elements are pivotably mounted. In one application, the
Easy Cover.RTM. System allows the tarp to be manually pulled in a
sweeping arc over the container load.
[0006] Another particular application of a similar tarping system
is generally depicted in FIG. 1. A vehicle 10, such as a dump
truck, can include an open-topped container body 11. The body
preferably includes a top rail 11b around its upper perimeter, and
a number of vertically oriented support ribs 11a.
[0007] A tarpaulin cover 13 is depicted in FIG. 1 in its deployed
configuration spanning the length of the container body 11. The
tarp can be preferably stowed by winding onto a tarp roller 14 at
the forward end of the vehicle. Both the tarp 13 and the roller 16
can be of a variety of known constructions, such as the Easy
Cover.RTM. Tarping System.
[0008] In the particular illustrated vehicle application, a bail
member 16 is mounted to the truck body 11 at a pivot mount 17. The
bail member 16 is attached to the free end of the tarp 13 and
arranged so that the pivoting travel of the bail member 16 moves
the tarp from its stowed to its deployed position. The bail member
22 is preferably U-shaped, and includes a pair of elongated arms 18
connected to the vehicle at the pivot mount 17.
[0009] It is understood that the vehicle 10 shown in FIG. 1
represents one type of hauling vehicle that utilizes a flexible
cover or tarping system. In other systems, the tarp is attached to
and supported by curved bows that span the width of the truck bed.
Like the system depicted in FIG. 1, the bow-type tarping system can
be manually or mechanically deployed, typically by pulling the end
of the tarp and sliding the bows along runners mounted to the top
rail 11 b the container body 11.
[0010] Regardless of the particular hauling vehicle application or
tarp configuration, one problem that is persistently faced is the
effect of air flow or wind as the vehicle is traveling. This
problem becomes especially acute at high speeds. The tarpaulin 13
is affected in a number of ways by the air flow across a traveling
vehicle 10. The front end of the vehicle creates turbulent air flow
that travels along the length of the container body 11. This
turbulence, which can be manifested by air vortices along the top
rail 11 b of the container body, has a tendency to lift the
flexible cover 13 away from the top of the body 11. A similar
result occurs due to the Bernoulli effect of the air passing over
the top of the vehicle. In essence, the tarp 13 acts as an air
foil, so that the air passing over the top of the tarp creates a
lower pressure zone, which again results in displacing the tarp
from the top of the container body 11.
[0011] All of these wind-related effects cause the tarp system and
flexible cover to bellow and flap. In addition, rough road
conditions can cause the tarp system, including its mechanical
elements, to bounce. While this action of the tarp and the
associated tarping system can be very noisy, the most deleterious
effect is on the flexible cover 13 itself. The constant bellowing
and flapping gradually wears the tarp down, which decreases its
longevity. In addition, when the tarp 13 bellows, the load within
the container body 11 is exposed to the elements.
[0012] In order to address this problem, various manually activated
systems have been devised. In one common system, a web of cords are
deployed over the cover 13 along the length of the container body
11. The ends of the cords can be attached to mounts fixed to the
side of the body. In other systems, the bail member, such as bail
member 16, can be activated to wrap the end of the cover over the
end of the vehicle body. These systems can be either manually or
mechanically operated, and can be tied down using a tie down rope
at the end of the body.
[0013] Still other systems rely upon a complicated array of
mechanical, electrical or hydraulic structures to apply a constant
tension along the length of the tarp. However, in most cases, the
tension along the length of the tarp does not alleviate the problem
of bellowing and flapping of the side edges of the tarp along the
top rail 11b of the vehicle body 11. In some cases, a tensioning
cable is threaded through eyelets along the side edges of the
flexible cover. These tension cables require some form of manual or
mechanical intervention to tightening the cables once the cover has
been deployed over the container body.
[0014] In spite of the many approaches to address the wind-related
damage to the cover tarp, these wind effects remain substantially
unchecked. All of the mechanical and rope-based systems have some
amount of play or give that is exploited by the previously
described wind effects, particularly at high vehicle speeds.
Consequently, what is needed is a hold-down mechanism positively
restrains the elements of the tarping system to counteract the
detrimental impact of the wind rushing across and through the
flexible tarp.
SUMMARY OF THE INVENTION
[0015] These problems are addressed by the present invention that
contemplates a hold-down locking mechanism that operates on
components of the cover deployment system. In certain embodiments,
the locking mechanism operates on the arms of the bail member that
is pivotably mounted to the container body. In other embodiments,
the locking mechanism operates on bow members integrated into the
flexible cover.
[0016] In one aspect of certain embodiments of the invention, the
hold-down locking mechanism includes a vane member that is
pivotably mounted to the side of the container body. The vane
member includes a locking element that engages another locking
element attached to an arm of the bail member when the bail member
is in its deployed position. The vane member is initially in a
neutral position adjacent the container body and apart from the
bail member arm. In its deployed position, the vane member locking
element prevents unwanted movement of the bail member arm.
[0017] In some embodiments of the invention, one important is that
the vane member is actuated by the force of air flowing past the
container body. This air flow can be due to wind blowing against a
stationary container or due to apparent wind created by a container
affiliated with a vehicle traveling above a certain road speed.
Thus, in these embodiments, air pressure is exerted against the
vane member to cause it to pivot from its neutral position to its
deployed or activated position.
[0018] In one specific embodiment, the vane member includes a
plate-like vane mounted to the container body by a hinge. The
leading edge of the vane can be angled to create a modest air foil,
thereby ensuring that air flow past the container body and vane
will generate an outwardly directed force on the vane, rather than
a force tending to push the vane into the container body. The vane
member can also include a locking bar that pivots with the vane.
The locking bar can engage a locking stop attached to an arm of the
bail member. In certain embodiments, the locking stop can define a
back stop and a rearwardly extending ramp that operates to increase
the downward force applied by the vane locking bar to the bail
member.
[0019] In a further aspect of certain embodiments, the vane member
includes a biasing means for biasing the vane to its neutral
position. In a specific embodiment, the biasing means can
constitute a spring disposed between the vane member and the
container body. The spring can be a torsion spring, extension
spring, or the like.
[0020] In another embodiment of the invention, the vane member is
attached to the arm of the bail member itself. In this embodiment,
the vane member acts against a locking or stop element attached to
the container body. In one specific embodiment, the vane member
includes a U-shaped pivot element that is pivotably attached to and
straddling the bail member arm. A vane is attached at one end of
the pivot element, while the opposite end of the element includes a
locking leg configuration. In this specific embodiment, the locking
leg configuration is adapted to engage a bar projecting outwardly
from the container body. With this embodiment, air flow or wind can
be used to move the vane member from its neutral position to a
position in which the locking leg configuration engages the locking
bar to prevent movement of the bail member arm.
[0021] In an alternative embodiment, the vane member can be
pivotably mounted to one side of the bail member arm. The vane
member in this embodiment can include a locking tab projecting
substantially perpendicularly from the back (downwind) face of the
vane. This locking tab is situated beneath a locking stop attached
to the container body when the vane member is pivoted to its
deployed position.
[0022] In another aspect of the invention, the hold-down locking
mechanism is adapted for use with a bow-type flexible cover system.
In embodiments of this aspect, a vane member can be pivotably
mounted to the container body adjacent an end of the tarp bow. The
locking mechanism in this embodiment also includes a hook that
pivots with the vane member. The hook is configured to catch and
retain the end of the tarp bow when the hook is in its actuated
position.
[0023] In an alternative embodiment, the vane member and hook are
separate components operably coupled through a gear train. The vane
member is connected to one gear that rotates as the vane member
pivots. The hook can be connected to a mating gear that rotates in
response to rotation of the vane member gear. The gear ratio can be
modified between the two gears to multiply the hold-down force
generated by pivoting of the vane member.
[0024] In certain embodiments of the invention, mechanical biasing
means are provided to bias the locking mechanism to its neutral
position. This biasing means can be overcome by a predetermined air
flow or air pressure being exerted on the vane member. When, for
example, the wind flow reaches a certain apparent speed, the force
exerted against the vane is sufficient to overcome the restoring
force of the biasing means, thereby allowing the vane member to
pivot to its deployed position. As the apparent wind speed
decreases below the threshold value, the biasing means draws the
vane member back to its neutral position.
[0025] In another feature, the biasing means can be replaced by a
gravity biasing arrangement. In this arrangement, the pivoting
components are sized and configured so that the vertically downward
force of gravity continuously acts on the pivoting elements to
guide them to a neutral position. In certain embodiments, the mass
of the vane member is adjusted to take advantage of this gravity
biasing aspect. In other embodiments, a separate mass can be
utilized to provide a gravity based restoring force to the pivoting
components of the locking mechanism.
[0026] It is one object of the present invention to provide an
active mechanism operable to hold a flexible cover on the open top
of a container body. A more specific object is to provide this
feature for hauling vehicles to overcome the nefarious effects of
wind and vibration as the vehicle is traveling.
[0027] One benefit of the invention is that it provides a simple
mechanism that can operate to restrain deployment components of a
flexible cover system. Another benefit is produced by certain
embodiments that operate automatically, such as at a predetermined
apparent wind speed.
[0028] These and other objects and benefits of the various
embodiments of the present invention can be appreciated upon
consideration of the following written description and accompanying
figures.
DESCRIPTION OF THE FIGURES
[0029] FIG. 1 is a top perspective view of a hauling vehicle
utilizing a flexible tarping system.
[0030] FIG. 2a is a side perspective view of a hold-down locking
mechanism according to one embodiment of the invention, with the
mechanism in its neutral position.
[0031] FIG. 2b is a side elevational view of the hold-down locking
mechanism shown in FIG. 2a, with the mechanism in its deployed
configuration.
[0032] FIGS. 3a and 3b are side elevational views of a hold-down
locking mechanism according to an alternative embodiment of the
invention, shown in its neutral and deployed position.
[0033] FIG. 4 is an end view of the mechanism shown in FIG. 3b.
[0034] FIGS. 5a and 5b are side elevational views of still another
embodiment of a hold-down locking mechanism according to the
present invention, depicted in its neutral and deployed
positions.
[0035] FIG. 6 is an end elevational view of the mechanism shown in
FIG. 5b.
[0036] FIG. 7 is a side elevational view of a hold-down locking
mechanism particularly suited for use with a bow-type tarping
system.
[0037] FIG. 8 is an alternative embodiment of a hold-down locking
mechanism for use with a bow-type tarping system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] For the purposes of promoting an understanding of the
principles of the invention, reference will now be made to the
embodiments illustrated in the drawings and specific language will
be used to describe the same. It will nevertheless be understood
that no limitation of the scope of the invention is thereby
intended. The invention includes any alterations and further
modifications in the illustrated devices and described methods and
further applications of the principles of the invention which would
normally occur to one skilled in the art to which the invention
relates.
[0039] The present invention contemplates a hold-down locking
mechanism operable to provide a restraining force against a
flexible cover to counteract effects of wind passing by the cover.
While the illustrated embodiments are particular adapted for use
for hauling vehicles, the same principals can be applied to
stationary open-topped containers utilizing flexible covers. In
addition, the illustrated embodiments more specifically pertain to
a dump truck hauling vehicle such as the truck 10 shown in FIG. 1.
Nevertheless, the same principals can be applied to a variety of
hauling vehicles having open-topped containers.
[0040] In one feature of the invention, a number of embodiments of
a hold-down locking mechanism are automatically actuated by air
flow across a vane member. The air flow causes the vane member to
move from a neutral position to a deployed or activated position.
In the deployed position, the vane member operates to positively
restrain or stop the movement of an element of the tarping system.
In the preferred embodiments, the vane member operates to restrain
movement of the bail member of a tarping deployment system.
[0041] Looking first at FIGS. 2a and 2b, the invention is embodied
in one form in a hold-down locking mechanism 20. This mechanism 20
includes a vane member 22 that is attached to the vehicle body 11
and a locking stop 24 that is attached to an arm 18 of the bail
member 16 (see FIG. 1). The vane member 22 includes a vane 26 that
is preferably in the form of a substantially rectangular plate. Of
course, other configurations of the vane 26 are contemplated, the
only requirement being that the vane have sufficient surface area
to "catch" the wind W flowing along the side of the vehicle body
11.
[0042] Preferably the vane 26 has a number of stiffening ribs 27
defined along its width. The vane 26 is mounted to the vehicle body
11 by way of a hinge 28. As shown by comparing FIG. 2a with FIG.
2b, the hinge 28 allows the vane 26 to move from its neutral
position (FIG. 2a) directly adjacent the vehicle body 11, to its
deployed position (FIG. 2b) extending substantially perpendicularly
from the container body.
[0043] In the preferred embodiment, the vane 26 defines a leading
edge 30 that is angled outwardly away from a pressure face 32 (see
FIG. 2b). The leading edge 30 allows the vane 26 to act in the
nature of an airfoil and ensures that the air pressure generated by
the wind W flowing along the side of the container body 11 does not
to act to push the vane 26 toward the body, rather than away from
the body to its deployed position shown in FIG. 2b. It can be
appreciated that when subject to an adequate amount of air
pressure, the vane gradually pivots along the hinge 28 away from
the container body 11. As the apparent wind flow continues, the air
pressure is exerted against the pressure face 32 to eventually push
the vane 26 to the position shown in FIG. 2b.
[0044] The vane member 22 further includes a locking bar 34 that
rotates with the vane 26. This locking bar 34 is configured to rest
within the locking stop 24. In the preferred embodiment, the
locking stop 24 is fixed to the arm 18 of the bail member 16. The
locking stop 24 can include a back stop face 36 that restricts
movement of the vane 26 back to its neutral position. In addition,
the stop 24 preferably includes a ramp 37. As the air pressure
generated by the wind W increases on the pressure face 32, the vane
26 pivots farther away from the container body 11. As the vane
continues to pivot, the locking bar 34 attempts to travel up the
ramp 37 of the locking stop 24. This additional travel increases
the amount of downward force applied to the arm 18. This increased
downward force can cause the bail member 16 to pivot about its
pivot mount 17, which motion increases the amount of tension
applied to the tarp 13 .
[0045] In a most preferred embodiment, a return spring 38 can be
disposed between the vane 26 and the container body 11. Most
preferably, the return spring 38 is in the form of one or more
torsion springs mounted along the hinge 28 and acting against the
downwind face 33 of the vane 26. The return spring 38 normally
operates to push the vane 26 back toward the container body 11, and
away from the bail member arm 18. The strength of the spring can be
calibrated to hold the vane 26 against the container body until a
pre-determined air flow rate or pressure has been reached. This
apparent wind or air flow rate can be achieved by the vehicle
traveling at a particular speed. For example, the return spring 38
can be calibrated to hold the vane in the neutral position shown in
FIG. 2a the vehicle reaches the speed of 15 mph.
[0046] In the preferred embodiment illustrated in FIGS. 2a and 2b,
the return spring 38 constitutes a torsion spring. Of course, other
biasing devices can be utilized, including alternative types of
springs. For example, a tension spring can be affixed between the
leading edge of the vane member and the container body. In
addition, the hinge 28 can be in the form of an elastic torsion bar
that is supported at its ends on the container body and permitted
to twist at its mid-point to which the vane is attached.
[0047] As further alternative of the preferred embodiment, the
locking stop 24 can be integrated into the surface of the arm 18.
In other words, the back stop and ramp feature can be formed
directly into the arm itself. As a further alternative, the vane 26
can engage the locking stop, thereby eliminating the locking bar
34. In this instance the bottom edge of the vane may be at least
slightly curved to facilitate its entrance in to and release from
the locking stop 24.
[0048] An alternative embodiment of the present invention is
depicted in FIGS. 3a, 3b and 4. In these figures, a hold-down
locking mechanism 40 is illustrated that includes a vane member 44
mounted to the arm 18 of the bail member 16. In this embodiment the
locking mechanism 40 includes a locking bar 42 that is attached to
and projects substantially perpendicularly from the container body
11. The vane member 44 is preferably attached to the arm 18 by way
of a mounting bracket 45. The mounting bracket 45 supports an axle
46 that engages a pivot element 49 of the vane member 44.
Preferably the pivot element 49 is a substantially U-shaped
bracket. A vane 47 is preferably affixed to the top of the U-shaped
of the pivot element 49.
[0049] The pivot element 49 further includes a pair of locking legs
51 projecting outward from the lower end of the U-shaped. Each
locking leg 51 can define a locking notch 52 that has a shaped
substantially conforming to the outer surface of the locking bar
42.
[0050] In its neutral position, as depicted in FIG. 3a, the vane
member 44 is pivoted slightly forward so that the locking legs 51
are clear of the locking bar 42. As the air pressure due to the
wind W increases, the pivot element 49 rotates to its actuated
position shown in FIG. 3b. In this position, the locking legs 51
are directly beneath the locking bar 42, most preferably with the
bar snugly disposed within the locking notch 52. Further wind
pressure applied against the vane 47 simply enhances the fixation
of the locking bar 42 to each of the locking legs 51 of the pivot
element 49.
[0051] As with the previous embodiment, some form of biasing means
can be provided to bias the vane member 44 to its neutral position
shown in FIG. 3a. In one specific embodiment, the mechanism 40 can
include a return spring 52, which in the illustrated embodiment is
in the form of a torsion spring mounted between the mounting
bracket 45 and the axle 46. Of course, other biasing mechanisms,
including springs, are contemplated, as suggested previously.
[0052] Referring to FIGS. 5a, 5b and 6, yet another embodiment of
the invention is illustrated. In these figures, a hold-down locking
mechanism 60 is also attached to the arm 18 of the bail member 16.
In this embodiment, the mechanism includes a vane member 62 and a
locking stop 64 that is mounted to the container body 11. The vane
member 62 includes a vane 66 that faces the air flow passing along
the side of the container body 11. A locking tab 68 projects from
the opposite surface of the vane, facing the locking stops 64.
Preferably, the locking tab 68 and vane 66 are shaped to generally
conform to the forward surface shape of the locking stop 64. As
shown in FIG. 5b, under action of the wind air flow, the vane
member 62 pivots rearwardly until the locking tab 68 is disposed
directly beneath the locking stop 64. The continued air pressure
holds the vane, and most particularly the locking tab 68, in this
deployed position. When the locking mechanism 60 is actuated, any
vertical movement of the arm 18 is prevented as the locking tab 68
contacts the locking stop 64.
[0053] Preferably the vane member 62 is pivotally mounted directly
to the arm 18, as shown in best in FIG. 6. In one preferred
embodiment, a pivot mount 70 is engaged to the under side of the
arm 18. An axle 71 projects outward form the pivot mount 70 and
through a pivot sleeve 72. The pivot sleeve 72 is attached to the
vane member 62. As with the previous embodiments, a biasing means
74 can be provided, which is preferably a torsional return spring
mounted between the pivot mount 70 and the axle 71.
[0054] The hold-down locking mechanisms 20, 40 and 60 of the
previous embodiments are most particularly suited for tarping
systems in which the tarp 13 is extended essentially flat across
the top of the container body. However, in some cases the tarping
system includes an array of transverse bows spanning the width of
the body to add some contour and height to the flexible tarp. While
similar hold-down locking mechanisms can be implemented for a
bow-type system, the present invention contemplates additional
embodiments specifically configured for this type of tarping
arrangement.
[0055] Most particularly a locking mechanism 80 as depicted in FIG.
7 is arranged to lock the tarp bow 78 to the top rail 11b of the
vehicle container body. In this embodiment the mechanism includes a
vane 82 that is pivotally mounted to the top rail 11b by way of a
pivot bar 83. The pivot bar can be affixed to a mounting bracket 85
to permit pivoting movements P of the vane in the direction of the
arrow T. The locking mechanism 80 further includes a hook 86 that
is attached to and rotates with the vane 82. As can be seen in FIG.
7, the hook 86 is configured to engage one end of the tap bow 78 as
the hook pivots in the direction of the arrow T. The shape and
arrangement of the hook 86 can be adapted according to the
structure of the end of the tarp bow 78.
[0056] As with the prior embodiments, the locking mechanism 80 of
FIG. 7 can include a mechanical biasing means such as a spring.
However, in the most preferred embodiment, the vane 82 is biased to
its neutral position shown in this figure by the weight of the
vane. As the vane 82 pivots in the direction of the arrow T away
from the depicted vertical position, gravity generates a restoring
force at the moving center of gravity of the vane. As long as the
air pressure generated by the wind flow exceeds this downward
force, the vane 82 will continue to pivot. However, once that air
flow falls below a certain threshold, gravity will again restore
the vane 82 to its vertical orientation. It is of course understood
that the weight of the vane and hook 86 can be calibrated so that
the vane only pivots to its locking position at a particular air
flow velocity, corresponding to a particular vehicle speed.
[0057] This same gravity feature can be implemented to provide a
restoring force to the vertically pivoting locking mechanisms 40
and 60 of FIGS. 3a-3b and 5a-5b, respectively. In both cases, the
vane members 44 can be flipped upside down from the orientation
shown in the figures, together with commensurate re-orientation of
the corresponding locking bar 34 or locking stop 64.
[0058] A locking mechanism 88 is illustrated in FIG. 8 that can be
used to engage and lock the end of a tarp bow 78. In this mechanism
a vane member 89 is independent of the locking member 90. The
locking member 90 can have the same hook configuration as the hook
86 in the embodiment of FIG. 7.
[0059] In this embodiment, movement of the vane member 89 is
transmitted to the locking member 90 through a gear train 91. In
the illustrated embodiment, two spur-type gears are pivotally
mounted to the container body pivoting the vane member 89 in the
direction of the arrow T, causes the right (driving) gear of the
gear train 91 to rotate in the direction R. This rotation causes a
commensurate rotation in the left (driven) gear of the gear train
which produces a corresponding pivoting movement of the locking
member 90 toward the tarp bow 78.
[0060] The gear ratio of gear train 91 can be adjusted to adjust
the holding force generated by movement of the vane member 89. For
instance, a larger driving gear can be attached to the vane member
89 so that a small incremental pivoting of the vane member can
yield a greater degree of pivoting of the locking member 90. When
the locking member is engaged to the tarp bow 78, this gear ratio
translates to the application of greater hold-down force applied to
the bow.
[0061] As with the prior embodiments, a mechanical or spring-type
biasing mechanism can be utilized to bias the vane member 89 and/or
locking member 90 to the neutral position shown in FIG. 8. However,
in the most preferred embodiment, a counter weight 93 is integrated
into either the vane member 89 or the locking member 90. As with
the embodiment of FIG. 7 the counter weight 93 reacts to the force
of gravity to provide a restoring force contrary to the direction
of rotation R of the gear train 91 or the direction of pivoting P
of the vane member 89. Again, the mass of this counter weight 93
can be adjusted to control the force required to activate the
locking mechanism 88.
[0062] While the invention has been illustrated and described in
detail in the drawings and foregoing description, the same is to be
considered as illustrative and not restrictive in character. It
should be understood that only the preferred embodiments have been
shown and described and that all changes and modifications that
come within the spirit of the invention are desired to be
protected.
[0063] For example, in all of the illustrated embodiments, the
hold-down locking mechanisms are wind or air pressure activated. In
an alternative approach, the vanes can be activated by human
intervention. With this approach, the vehicle operator, for
instance, can determine whether wind and traveling conditions are
causing a problem with the container cover system.
[0064] In one embodiment of this human intervention approach, the
locking elements can be deployed by activating a mechanical linkage
or cable system. For instance, a cable can be linked to the vane
member 22 of the embodiment of FIGS. 3a, b. Pulling the cable can
cause the vane member to pivot into its deployed position. A
similar cable arrangement can be employed with the locking
mechanisms 40, 60, 80, and 88.
[0065] As a further alternative, the vane members can be
electrically or hydraulically actuated. For instance, a vane member
cen be connected to a rotary solenoid or motor operable to rotate
the locking mechanism into its deployed position.
* * * * *