Note: Descriptions are shown in the official language in which they were submitted.
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Title: Conveyor Apparatus for Loading or Unloading Packages From
Shipping Containers
Technical Field
[0001] The invention relates to a conveyor apparatus for unloading
containers,
and in particular, a conveyor apparatus removably connectable to an extendable
conveyor for unloading shipping containers such as truck trailers.
Background
[0002] Modern supply networks utilize distribution centers to
temporarily store
products before distributing them to wholesalers, retailers, or directly to
consumers.
As a result, distribution centers receive a vast amount of products on a daily
basis
and many of these products arrive in packages on transport trucks. These
packages
are unloaded and then placed on a conveyor system, which sorts and routes the
packages to different areas within the distribution center for later
distribution. In
many cases, these packages are unloaded using manual labor.
[0003] A common problem with many distribution centers is that employees can
injure themselves while unloading the packages from truck trailers. For
example,
trailers are often filled with packages from the floor to ceiling and
employees
sometimes strain themselves when repeatedly bending over to pick up the
bottommost packages, and/or reaching up to grab the topmost packages. These
repeated physical strains can cause short and long-term injuries. Even the
seemingly simple task of carrying packages within the trailer can be
hazardous,
particularly with heavier packages. Accordingly, it is desirable to provide
equipment
that reduces health and safety concerns associated with unloading trailers.
[0004] There have been some attempts to provide equipment that assists
employees while loading and unloading packages from trailers. Many of these
solutions utilize an extendable conveyor that can be positioned inside the
trailer so
that an employee can pick and place packages on the extendable conveyor
without
having to carry the package out of the trailer. The extendable conveyor then
transports the package to a conveyor system within the distribution center.
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[0005] One example of an extendable conveyor is described in U.S.
Patent No.
6,431,346 (Gilmore et al.). The conveyor includes an extendable conveyor
section
and a user interface section supported in cantilever fashion on the end of the
extendable conveyor section. The user interface is vertically adjustable about
a
horizontal axis and horizontally adjustable about a vertical axis. According
to
Gilmore et al., providing a user interface section that pivots from side-to-
side, and up
and down, helps an operator load packages at different lateral positions and
different
heights within the trailer.
[0006] While the user interface section of the Gilmore et al.
conveyor moves up
and down, employees can still strain themselves when reaching for packages
near
the floor and ceiling. Furthermore, the entire conveyor, including the user
interface
section, has limited weight capacity because it is supported in a cantilever
fashion.
The packages also tend to jam when transitioning from the user interface
section to
the extendable section, particularly when the user interface section has been
pivoted
to one side. In some cases, packages might even fall off the conveyor when
transitioning from the user interface section to the extendable section.
[0007] Accordingly, there is a need for an improved conveyor
apparatus, which
overcomes one or more of the disadvantages associated with the prior art.
Summary of the Invention
[0008] According to one aspect of the invention, there is provided a
conveyor
apparatus comprising a frame removably connectable to an extendable conveyor,
and a pivoting conveyor coupled to the frame. The pivoting conveyor includes a
slewing conveyor section pivotally coupled to the frame for pivotal movement
about
a generally vertical axis, and a tiltable conveyor section. The tiltable
conveyor
section has one end pivotally coupled to the slewing conveyor section for
pivotal
movement about a generally horizontal axis, and an opposing free end shaped
for
receiving objects. The tiltable conveyor section includes a first conveying
surface for
conveying the objects between the free end of the tiltable conveyor section
and the
slewing conveyor section. The slewing conveyor section includes a second
conveying surface for conveying the objects between the tiltable conveyor
section
and the extendable conveyor. The free end of the tiltable conveyor section can
be
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moved from side-to-side by pivoting the slewing conveyor section about the
vertical
axis. The free end of the tiltable conveyor section can also be moved up and
down
by pivoting the tiltable conveyor section about the horizontal axis
independent of the
slewing conveyor section.
[0009] The apparatus may further comprise an operator platform coupled to
the
frame and located below the free end of the tiltable conveyor section for
supporting
an operator. The operator platform is configured to move vertically relative
to the
frame so as to position the operator at a user adjustable height. The
apparatus may
also comprise a platform elevation mechanism coupled between the frame and the
operator platform for raising and lowering the operator platform. Furthermore,
the
apparatus may comprise a safety lock mechanism for securing the operator
platform
at the user adjustable height. The apparatus may further comprise a conveyor
lifting
mechanism coupled to the frame and the slewing conveyor section for raising
and
lowering the pivoting conveyor relative to the frame.
[0010] The frame may include a base supported by wheels. At least some of the
wheels may be motorized wheels for driving the frame.
[0011] The apparatus may also comprise a counter balance mechanism coupled
to the slewing conveyor section and the tiltable conveyor section for
counteracting
the weight of the tiltable conveyor section. In some embodiments, the weight
of the
tiltable conveyor section creates a first moment of force about the horizontal
axis,
and the counter balance mechanism may comprise an air cylinder pivotally
coupled
to the slewing conveyor section and pivotally coupled to the tiltable conveyor
section. The air cylinder is configured to apply a force to the tiltable
conveyor section
so as to create a second moment of force about the horizontal axis that is
approximately equal and opposite to the first moment of force.
[0012] The apparatus may comprise a first brake assembly coupled to the frame
and the slewing conveyor section for selectively inhibiting pivotal movement
of the
slewing conveyor section about the vertical axis. The apparatus may comprise a
second brake assembly coupled to the slewing conveyor section and the tiltable
conveyor section for selectively inhibiting pivotal movement of the tiltable
conveyor
section about the horizontal axis.
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[0013] The apparatus may also comprise a flexible conveyor extending
from the
slewing conveyor section toward the extendable conveyor. The flexible conveyor
is
configured to curve from side-to-side so as to provide a flexible transition
zone
between the slewing conveyor section and the extendable conveyor when pivoting
the slewing conveyor section about the vertical axis.
[0014] In some embodiments, the slewing conveyor section conveys
packages
along a first pivoting longitudinal axis and the extendable conveyor conveys
packages along a second fixed longitudinal axis. The flexible conveyor may
have a
first end proximal to the slewing conveyor section and defining a first
transverse axis
that remains generally perpendicular to the first pivoting longitudinal axis
when the
slewing conveyor section pivots about the vertical axis, and a second end
proximal
to the extendable conveyor and defining a second transverse axis that remains
generally perpendicular to the second fixed longitudinal axis when the slewing
conveyor section pivots about the vertical axis. The apparatus may also
comprise an
anchor bar removably coupled to the frame and the second end of the flexible
conveyor so as to maintain alignment of the second end of the flexible
conveyor with
the second fixed longitudinal axis.
[0015] The flexible conveyor may include a pair of side frames spaced
apart from
each other. Each side frame includes a plurality of interconnected links
configured
so that each side frame can expand and contract independently of the other
side
frame so as to provide the flexible transition zone between the slewing
conveyor
section and the extendable conveyor. The flexible conveyor may also include a
plurality of rollers interposed between the side frames. The rollers are
rotatably
coupled to opposing pairs of the interconnected links on each side frame. The
rollers
are configured to convey objects between the slewing conveyor section and the
extendable conveyor.
[0016] The flexible conveyor may extend outward from the slewing conveyor
section and may decline toward the extendable conveyor so as to gravity feed
objects from the slewing conveyor section to the extendable conveyor.
Furthermore,
the frame may include a conveyor lifting mechanism for raising and lowering
the
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pivoting conveyor relative to the frame so as to maintain a declining slope
from the
slewing conveyor section to the extendable conveyor.
[0017] According to another aspect of the invention, there is
provided a conveyor
apparatus for loading and unloading objects from a shipping container. The
conveyor apparatus comprises a frame removably connectable to an extendable
conveyor, and a pivoting conveyor coupled to the frame. The pivoting conveyor
includes a slewing conveyor section pivotally coupled to the frame for pivotal
movement about a generally vertical axis, and a tiltable conveyor section. The
tiltable conveyor section has one end pivotally coupled to the slewing
conveyor
section for pivotal movement about a generally horizontal axis, and an
opposing free
end shaped for receiving the objects being loaded into or unloaded from the
shipping
container. The tiltable conveyor section includes a first conveying surface
for
conveying the objects between the free end of the tiltable conveyor section
and the
slewing conveyor section. The slewing conveyor section includes a second
conveying surface for conveying the objects between the tiltable conveyor
section
and the extendable conveyor. The free end of the tiltable conveyor section can
be
moved from side-to-side by pivoting the slewing conveyor section about the
vertical
axis. The free end of the tiltable conveyor section can also be moved up and
down
by pivoting the tiltable conveyor section about the horizontal axis
independent of the
slewing conveyor section. The apparatus also comprises an operator platform
coupled to the frame and located below the free end of the tiltable conveyor
section
for supporting an operator while loading the objects into or unloading the
objects
from the shipping container. The operator platform is configured to move
vertically
relative to the frame so as to position the operator at a user adjustable
height.
[0018] According to another aspect of the invention, there is provided a
conveyor
apparatus comprising a frame removably connectable to an extendable conveyor,
and a pivoting conveyor coupled to the frame for conveying objects to or from
the
extendable conveyor. The pivoting conveyor includes a first pivotable conveyor
section having a free end shaped for supporting objects and having a first
conveying
surface for conveying objects to or from the free end. The first pivotable
conveyor
section is pivotally coupled to the frame about a vertical axis for pivoting
the free end
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from side-to-side and pivotally coupled to the frame about a first horizontal
axis for
pivoting the free end up and down. The pivoting conveyor also includes a
second
non-pivotable conveyor section having a second conveying surface for conveying
the objects to or from the first pivotable conveyor section, and a plurality
of transition
plates located between the first and second conveying surfaces for
transferring
objects therebetween. The transition plates include a fixed transition plate
located
adjacent to the second conveying surface, and a shuttling transition plate
located
adjacent to the first conveying surface and configured to move laterally
relative to
the first conveying surface as the first pivotable conveyor section pivots
about the
vertical axis.
[0019] According to another aspect of the invention, there is
provided a conveyor
apparatus comprising a frame removably connectable to an extendable conveyor,
and a pivoting conveyor coupled to the frame for conveying objects to or from
the
extendable conveyor. The pivoting conveyor includes a first pivotable conveyor
section having a free end shaped for supporting objects and having a first
conveying
surface for conveying objects to or from the free end. The first pivotable
conveyor
section is pivotally coupled to the frame about a vertical axis for pivoting
the free end
from side-to-side and pivotally coupled to the frame about a first horizontal
axis for
pivoting the free end up and down. The pivoting conveyor also includes a
second
non-pivotable conveyor section having a second conveying surface for conveying
the objects to or from the first pivotable conveyor section, and a third
tiltable
conveyor section having a third conveying surface for conveying the objects
between the second non-pivoting conveyor and the extendable conveyor. The
third
tiltable conveyor section has a rear end for being connected to the extendable
conveyor. The third tiltable conveyor section is pivotally coupled to the
frame about a
second horizontal axis for pivoting the rear end up and down.
[0020] According to another aspect of the invention, there is
provided a conveyor
apparatus comprising a frame removably connectable to an extendable conveyor,
and a pivoting conveyor coupled to the frame for pivotal movement about a
generally
vertical axis and for pivotal movement about a generally horizontal axis. The
pivoting
conveyor has a free end shaped for receiving objects. The pivoting conveyor
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includes at least one conveying surface for conveying the objects between the
free
end and the extendable conveyor. Furthermore, the free end can be moved from
side-to-side by pivoting the pivoting conveyor about the vertical axis, and
the free
end can be moved up and down by pivoting the pivoting conveyor about the
horizontal axis. The pivoting conveyor also has a weight. The conveyor
apparatus
also includes a counter balance mechanism coupled to the pivoting conveyor for
counteracting the weight of the pivoting conveyor.
[0021] Other aspects and features of the invention will become
apparent, to those
ordinarily skilled in the art, upon review of the following description of
some
exemplary embodiments.
Brief Description of the Drawings
[0022] The drawings included herewith are for illustrating various
examples of
methods and apparatus of the present specification and are not intended to
limit the
scope of what is taught in any way. In the drawings:
[0023] FIG. 1 is a perspective view of a conveyor apparatus according
to an
embodiment of the present invention;
[0024] FIG. 2 is a side elevation view of the conveyor apparatus of
FIG. 1, in
which a tiltable conveyor section of the pivoting conveyor pivots up and down
between three positions;
[0025] FIG. 3 is a top plan view of the conveyor apparatus of FIG. 1, in
which the
pivoting conveyor is pivoting from side-to-side between two positions;
[0026] FIG. 4 is an exploded perspective view of the frame including
a slewing
bearing for attachment to a slewing conveyor section of the pivoting conveyor;
[0027] FIG. 5 is an exploded perspective view of the slewing
conveyor section of
the pivoting conveyor;
[0028] FIG. 6 is an exploded perspective view of the tiltable
conveyor section of
the pivoting conveyor;
[0029] FIG. 7 is a perspective view of the flexible conveyor;
[0030] FIG. 8 is a side elevation view of the conveyor apparatus
attached to an
extendable conveyor and approaching a truck trailer on a loading dock;
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[0031] FIG. 9 is a side elevation view of the conveyor apparatus being
raised on
a dock lever and into the truck trailer;
[0032] FIG. 10 is a side elevation view of the conveyor apparatus being
advanced into the truck trailer by extension of the extendable conveyor;
[0033] FIG. 11 is a side elevation view of the conveyor apparatus with the
pivoting conveyor being raised relative to the frame, and an operator platform
being
raised relative to the frame;
[0034] FIG. 12 is a side elevation view of the conveyor apparatus, in which
the
tiltable conveyor section of the pivoting conveyor has been pivoted upward;
[0035] FIG. 13 is a side elevation view of a conveyor apparatus according
to
another embodiment of the present invention;
[0036] FIG. 14 is a perspective view of a conveyor apparatus according to
another embodiment of the present invention;
[0037] FIG. 15 is a side elevation view of the conveyor apparatus of FIG.
14;
[0038] FIG. 16 is an exploded perspective view of a pivoting conveyor of
the
conveyor apparatus of FIG. 14;
[0039] FIGS. 17A, 17B, and 17C are top plan views of the conveyor apparatus
of
FIG. 14, in which the pivoting conveyor has been pivoted from side-to-side in
three
different positions;
[0040] FIG. 18 is a perspective view of an operator platform and platform
elevation mechanism of the conveyor apparatus of FIG. 14;
[0041] FIG. 19 is a cross-sectional view of a first pivotable conveyor
section of
the conveyor apparatus of FIG. 14; and
[0042] FIG. 20 is a perspective view of the conveyor apparatus of FIG. 14
reconfigured for unloading a shipping container.
Detailed Description of the Invention
[0043] Referring to FIG. 1, illustrated therein is a conveyor apparatus 20
made in
accordance with an embodiment of the present invention. Generally, an operator
uses the conveyor apparatus 20 to unload packages or other objects from a
shipping
container, such as a truck trailer, and onto an extendable conveyor 16, which
may
route the packages to different areas in a facility such as a distribution
center. The
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extendable conveyor 16 includes three sections 18a, 18b, and 18c
telescopically
nested within each other, and a conveyor belt extending along the sections
18a,
18b, and 18c for conveying packages from the first section 18a toward the
third
section 18c. As known in the art, the length of the belt increases or
decreases as the
sections 18a, 18b, and 18c extend and retract from each other. While the
illustrated
extendable conveyor has three sections, it should be understood that the
extendable
conveyor may have a different number of sections, and that the conveyor
apparatus
20 may be used with other types of conveyors, such as extendable roller
conveyors,
fixed length belt conveyors, and the like.
[0044] The conveyor apparatus 20 includes a frame 22 connectable to the
extendable conveyor 16, a pivoting conveyor 24 pivotally coupled to the frame
22 for
unloading packages from the truck trailer, and a flexible conveyor 30
extending from
the pivoting conveyor 24 toward the extendable conveyor 16 for conveying
packages
from the pivoting conveyor 24 to the extendable conveyor 16. While the
conveyor
apparatus 20 typically includes guarding for protecting the operator and
addressing
other safety concerns, the guarding is not shown in the illustrated embodiment
for
clarity.
[0045] The pivoting conveyor 24 includes two conveyor sections,
namely, a
generally horizontal slewing conveyor section 26 pivotally coupled to the
frame 22
for pivotal movement about a vertical axis V, and a tiltable conveyor section
28
having a proximal end pivotally coupled to the slewing conveyor section 26 for
pivotal movement about a horizontal axis H. The tiltable conveyor section 28
also
has an opposing free end 32 shaped for receiving packages being unloaded from
the truck trailer. Generally, the horizontal axis H of the tiltable conveyor
section 28 is
located between the free end 32 of the tiltable conveyor section 28 and the
vertical
axis V of the slewing conveyor section 26.
[0046] Each of the conveyor sections 26 and 28 have conveying
surfaces for
conveying packages from the free end 32 toward the extendable conveyor 16. In
particular, the tiltable conveyor section 28 includes a first conveying
surface 40 for
conveying packages from the free end 32 toward the slewing conveyor section
26,
and the slewing conveyor section 26 includes a second conveying surface 42 for
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conveying packages from the tiltable conveyor section 28 toward the extendable
conveyor 16.
[0047] In the
illustrated embodiment, the conveying surfaces 40 and 42 are the
top surfaces of endless conveyor belts, which may be made from rubber or
another
suitable material. Each endless belt is reeved around rollers and is powered
by an
electric motor coupled to one of the rollers as will be described below. In
other
embodiments, the conveying surfaces 40 and 42 may have other configurations,
such as the top surfaces of powered rollers, plastic belt conveyors, slat
conveyors,
and the like.
[0048] Generally,
pivoting the slewing conveyor section 26 from side-to-side
about the vertical axis V adjusts the lateral position of the free end 32 of
the tiltable
conveyor section 28 so that an operator can place the free end 32 at a lateral
position corresponding to a package being unloaded from a truck trailer.
Furthermore, pivoting the tiltable conveyor section 28 up and down about the
horizontal axis H adjusts the vertical position of the free end 32 of the
tiltable
conveyor section 28 so that an operator can place the free end 32 at a height
corresponding to a package being unloaded from the truck trailer. Moving the
free
end 32 to various positions corresponding to each individual package generally
reduces physical strains that an operator might sustain if the free end had a
fixed
position.
[0049] In the
illustrated embodiment, the operator manually moves the free end
32, for example, by grasping handles 34 located proximal to the free end 32 on
the
tiltable conveyor section 28. After moving the free end 32 to a desired
position, the
tiltable conveyor section 28 and the slewing conveyor section 26 may be locked
in
position to inhibit further pivotal movement about the vertical axis V and/or
the
horizontal axis H, as will be described below. In other embodiments, the
apparatus
may include actuators (e.g. hydraulic, electronic, or pneumatic actuators)
that
provide powered movement of the free end 32. For example, a first actuator may
be
configured to pivot the tiltable conveyor section 28 about the horizontal axis
H, and a
second actuator may be configured to pivot the slewing conveyor section 26
about
the vertical axis V.
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[0050] Referring to FIG. 2, the tiltable conveyor section 28 pivots up
and down
within a range of elevations corresponding to the elevation angle 50. As
shown, the
elevation angle 50 may extend from between about -35 to about +35 from the
horizontal. In other embodiments, the elevation angle 50 may be different.
[0051] Referring to FIG. 3, the slewing conveyor section 26 pivots from
side-to-
side through a range of positions corresponding to the azimuth angle 52. As
shown,
the azimuth angle 52 may be about 40 , namely, between -20 and +20 from the
longitudinal axis 56. In other embodiments, the azimuth angle 52 may be
different.
[0052] As shown in FIG. 3, the tiltable conveyor section 28 generally
pivots with
the slewing conveyor section 26 about the vertical axis V. In other words,
when
pivoting the slewing conveyor section 26 about the vertical axis V, the entire
pivoting
conveyor 24 pivots as a unit, including both the tiltable conveyor section 28
and the
slewing conveyor section 26.
[0053] In contrast, the tiltable conveyor section 28 generally pivots
about the
horizontal axis H independently of the slewing conveyor section 26. In other
words,
when pivoting the tiltable conveyor section 28, the slewing conveyor section
26
maintains a generally horizontal orientation and does not tilt up or down.
[0054] Maintaining the horizontal orientation of the slewing conveyor
section 26
tends to provide a gradual transition for packages moving from the pivoting
conveyor
24 to the flexible conveyor 30. Without the horizontal slewing conveyor
section 26,
packages might be subject to a sudden change in inclination when moving from
the
pivoting conveyor 24 to the flexible conveyor 30. For example, if the tiltable
conveyor
section 28 were tilted downward to the free end 32, and the flexible conveyor
30
were tilted downward to the extendable conveyor 16, packages being propelled
upward on the pivoting conveyor 24 would suddenly change direction and would
begin falling downward on the flexible conveyor 30. This sudden change of
direction
might damage packages, or cause them to jam or fall off the conveyors,
particularly
when the slewing conveyor section 26 is pivoted to one side. The horizontal
slewing
conveyor section 26 provides a more gradual change in inclination/declination
by
remaining horizontal, which tends to reduce the likelihood of damaging
packages or
causing packages to jam or fall off the conveyors.
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[0055]
Referring again to FIG. 1, the flexible conveyor 30 is configured to convey
packages from the slewing conveyor section 26 to the extendable conveyor 16.
In
the illustrated embodiment, the flexible conveyor 30 is a gravity feed
conveyor and
includes a plurality of rollers extending from the slewing conveyor section 26
and
downward to the extendable conveyor 16. Accordingly, packages leaving the
powered conveying surface 42 of the slewing conveyor section 26 travel down
the
flexible conveyor 30 toward the extendable conveyor 16 under the force of
gravity. In
other embodiments, the flexible conveyor 30 may include powered rollers, or
another
powered conveying surfaces instead of being a gravity feed conveyor.
[0056] In the
illustrated embodiment, the flexible conveyor 30 is pivotally coupled
to the slewing conveyor section 26 along a second horizontal axis F, which
allows
the flexible conveyor 30 to pivot up and down relative to the pivoting
conveyor 24. In
other embodiments, the flexible conveyor 30 may be rigidly coupled to the
slewing
conveyor section 26.
[0057] The
flexible conveyor 30 generally provides a flexible transition zone
between the slewing conveyor section 26 and the extendable conveyor 16, which
allows packages to gradually change directions when transitioning from the
slewing
conveyor section 26 to the extendable conveyor 16. For example, referring to
FIG 3,
the slewing conveyor section 26 generally conveys packages along a first
pivoting
longitudinal axis 54, and the extendable conveyor 16 conveys packages along a
second fixed longitudinal axis 56. When the slewing conveyor section 26 pivots
from
side-to-side, the first pivoting longitudinal axis 54 pivots relative to the
second fixed
longitudinal axis 56, which would normally represent a sudden change in
direction
for packages transitioning from the slewing conveyor section 26 to the
extendable
conveyor 16. The flexible conveyor 30 compensates for this change in direction
by
curving to one side, which gradually turns the packages along the flexible
conveyor
30.
[0058] More
particularly, the flexible conveyor 30 has a first end 60 proximal to
the slewing conveyor section 26 and a second end 62 proximal to the extendable
conveyor 16. The first end 60 defines a first transverse axis 61, which
remains
generally perpendicular to the first pivoting longitudinal axis 54
corresponding to the
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slewing conveyor section 26. The second end 62 defines a second transverse
axis
63, which remains generally perpendicular to the second fixed longitudinal
axis 56
corresponding to the extendable conveyor 16. The middle of the flexible
conveyor 30
between the two ends 60 and 62 curves from side-to-side to maintain alignment
of
the first end 60 with the first pivoting longitudinal axis 54, and alignment
of the
second end 62 with the second fixed longitudinal axis 56. For example, as
shown in
FIG. 3, when the slewing conveyor section 26 pivots counter-clockwise, the
middle
of the flexible conveyor 30 curves into an S-shape so as to maintain alignment
of the
first end 60 with the first pivoting longitudinal axis 54, and alignment of
the second
end 62 with the second fixed longitudinal axis 56.
[0059] Without the flexible conveyor 30, packages transitioning from the
slewing
conveyor section 26 to the flexible conveyor 30 might jam due to the sudden
change
in direction, particularly when the slewing conveyor section 26 pivots to one
side. In
some cases, packages might even fall over the edge of the extendable conveyor
16
during the transition. The flexible conveyor 30 tends to prevent jams and
fallen
packages by providing a flexible transition zone that conveying packages from
the
slewing conveyor section 26 to the extendable conveyor 16.
[0060] It will be understood that when the slewing conveyor section 26
has not
been pivoted to either side, the first pivoting longitudinal axis 54 will be
generally co-
linear to the second fixed longitudinal axis 56, and the flexible conveyor 30
will be
generally straight.
[0061] Referring now to FIGS. 4-7, the frame 22, the slewing conveyor
section
26, the tiltable conveyor section 28, and the flexible conveyor 30 will now be
described in further detail.
[0062] Referring to FIG. 4, the frame 22 includes a base 70 supported by
wheels
72, which may be caster wheels. Generally, the wheels at least partially
support the
conveyor apparatus 20, and enable the conveyor apparatus 20 to carry heavier
packages in comparison to prior art cantilever supported conveyors, such as
the
extendable conveyor of Gilmore et al. In some embodiments, the wheels 72 may
be
powered and the conveyor apparatus 20 may be operated as a drivable vehicle.
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[0063] The conveyor apparatus 20 also includes an operator platform
74 coupled
to the frame 22 and located below the free end 32 of the tiltable conveyor
section 28
(see FIG. 1). Generally, the operator platform 74 is configured to support an
operator
while unloading packages from the truck trailer and onto the tiltable conveyor
section
28. In some embodiments, the top surface of the operator platform 74 may be
covered with an anti-fatigue rubber mat so as to reduce operator fatigue.
[0064] The operator platform 74 is coupled to two front posts 70a
that extend
upwardly from the base 70 of the frame 22. More particularly, the conveyor
apparatus 20 includes a platform elevation mechanism 75 for coupling the
operator
platform 74 to the front posts 70a. The platform elevation mechanism 75 allows
the
operator platform 74 to move up and down along the posts 70a so as to position
the
operator at a user adjustable height while unloading packages from the truck
trailer.
For example, the operator platform 74 can be positioned by the operator at a
height
that allows the operator to ergonomically unloading packages from the truck
trailer
without significant physical strains.
[0065] The platform elevation mechanism 75 includes an elevation
actuator, such
as a hydraulic cylinder (not shown) located within the front posts 70a and
coupled to
the operator platform 74, for example using a cable and pulley (not shown)
that are
also located within the front posts 70a.
[0066] The platform elevation mechanism 75 also includes lift brackets
76 for
slidably supporting the operator platform 74 on the front posts 70a. The lift
brackets
76 are generally coupled to corresponding mounting plates on the operator
platform
74. Each lift bracket 76 has a generally C-shaped cross-section sized to fit
around a
respective post 70a, and two grooves that receive corresponding protruding
edges
78 on the sides the respective post 70a. The grooves and protruding edges 78
cooperate to support and guide the operator platform 74 as it moves up and
down
along the posts 70a. Each lift bracket 76 may also include rollers that engage
the
edges 78 to facilitate sliding movement up and down the front posts 70a. In
other
embodiments, the operator platform 74 may be supported in other ways, and may
be
raised and lowered using other actuators, such as pneumatic or electric
actuators.
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=
[0067] The platform elevation mechanism 75 also includes a safety
lock
mechanism (not shown) for securing the operator platform 74 at a specific
height, for
example, in the event that the elevation actuator fails. In some embodiments,
the
safety lock mechanism includes a hydraulic cylinder (not shown) having an
operating
valve and a down flow restrictor for preventing sudden movements of the
operator
platform 74, such as falls due to a failure. The safety lock mechanism may
also
include a redundant load chain (not shown) for backing up cable and wire rope
failure of the elevation actuator. Furthermore, the safety lock mechanism may
include a drop safety lock mechanism (not shown) located on the cylinder posts
to
protect against mechanical failure of the chain and cylinder mechanism. The
drop
safety lock mechanism may include a ratchet (not shown) that engages a
corresponding set of teeth (not shown) extending vertically along one of the
front
posts 70a. Alternatively, the drop safety lock mechanism may be in the form of
a
locking pin (not shown) extending through one of a plurality of apertures (not
shown)
in the front posts 70a so as to support the lift brackets 76.
[0068] The conveyor apparatus 20 also includes a lift frame 80
coupled to a pair
of rear posts 70b of the frame 22 for supporting the slewing conveyor section
26 of
the pivoting conveyor 24. In particular, the lift frame 80 includes a pair of
posts 81
parallel to the rear posts 70b and slidably coupled thereto using lift
brackets 86,
which are generally similar to the lift brackets 76.
[0069] A slewing bearing 82 is attached to the top of the lift frame
80 for pivotally
coupling the slewing conveyor section 26 to the frame 22. In particular, the
slewing
bearing 82 includes an outer ring 82a fastened to a corresponding bearing
spacer 84
(shown in FIG. 5), which is fastened to the underside of the slewing conveyor
section 26. As known in the art, the outer ring 82a of the slewing bearing 82
is
rotatably supported on an inner ring 82b through a plurality of ball bearings
(not
shown), which allows smooth rotation of the slewing bearing 82. The central
axis of
the slewing bearing 82 generally defines the vertical axis V.
[0070] The conveyor apparatus 20 also includes a conveyor lifting
mechanism 85
coupled between the rear posts 70b and the posts 81 of the lift frame 80 for
raising
and lowering the pivoting conveyor 24 relative to the frame 22. The conveyor
lifting
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=
mechanism 85 is similar in many respects to the platform elevation mechanism
75,
and includes a lifting actuator (not shown) and lift brackets 86 (similar to
lift brackets
76) for slidably supporting the lift frame 80 on the rear posts 70b.
[0071] The lifting mechanism 85 may be used to raise and lower the
slewing
conveyor section 26 of the pivoting conveyor 24 so as to maintain a gradual
declining slope from the slewing conveyor section 26 to the extendable
conveyor 16.
This may be useful when the flexible conveyor 30 is a gravity feed conveyor,
which
typically requires at least a moderate slope to convey packages toward the
extendable conveyor 16.
[0072] An operator might also raise or lower the slewing conveyor section
26 in
order to position the free end 32 of the tiltable conveyor section 28 at a
specific
height for unloading packages. In particular, it might be desirable to raise
the slewing
conveyor section 26 in order to reach packages located near the ceiling of a
truck
trailer, or to lower the slewing conveyor section 26 in order to reach
packages
located near the floor.
[0073] The conveyor apparatus 20 may also include controls (not
shown) for
operating the platform elevation mechanism 75 and the conveyor lifting
mechanism
85. The controls may be located on the frame 22 so that an operator standing
on the
operator platform 74 can control the vertical position of both the operator
platform 74
and the pivoting conveyor 24. For example, the controls may be located on one
or
both of the front posts 70a. Alternatively, the controls may be operated via a
wired or
wireless remote.
[0074] The conveyor apparatus 20 also includes a power unit 90 mounted to the
frame 22 for providing power to various components on the conveyor apparatus
20,
such as the elevation mechanism 75, the lifting mechanism 85, brake calipers
102
and 142, motors 118 and 168, and the like. The power unit 90 may include a
hydraulic pump, an electrical power supply, a pneumatic supply, and/or another
type
of power unit. The power unit 90 may be enclosed by a removable housing 92.
[0075] A link bar assembly 94 is also pivotally coupled to the base
70 for
connecting the frame 22 to the extendable conveyor 16. For example, as shown
in
FIG. 1, the link bar assembly 94 may be coupled to the lower front end of the
first
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section 18a of the extendable conveyor 16 using mounting blocks 96. Generally,
the
frame 22 remains coupled to the extendable conveyor 16 during use, even after
unloading one truck trailer and then moving into a subsequent truck trailer.
However,
it will be understood that the mounting blocks 96 are removably coupled to the
extendable conveyor 16 so that the conveyor apparatus 20 can be detached from
one extendable conveyor and then attached to a different extendable conveyor.
[0076] Referring now to FIG. 5, the slewing conveyor section 26 includes
a base
100 that supports the conveying surface 42 and other components of the slewing
conveyor section 26. The underside of the base 100 is fastened to the bearing
spacer 84, which is in turn fastened to the slewing bearing 82 (shown in FIG.
4) for
pivotally coupling the slewing conveyor section 26 to the frame 22 along the
vertical
axis V. This allows an operator to pivot the slewing conveyor section 26 about
the
vertical axis V so as to position the free end 32 of the tiltable conveyor
section 28 in
a desired lateral position.
[0077] A pair of brake calipers 102 is attached to the underside of the
base 100
for locking the slewing conveyor section 26 in a desired position. The brake
calipers
102 releasably engage a corresponding pair of brake discs 104 (shown in FIG.
4)
located on the top of the lift frame 80 on opposing sides of the slewing
bearing 82.
The brake calipers 102 disengage the brake discs 104 while pivoting the
slewing
conveyor section 26 about the vertical axis V. When the slewing conveyor
section 26
has been rotated to a desired position, the brake calipers 102 frictionally
engage the
brake discs 104 and inhibit further movement.
[0078] In the illustrated embodiment, the brake calipers 102 are
pneumatically
operated. In other embodiments, the brake calipers 102 may be powered by
alternative power sources, such as hydraulic or electrical energy.
Furthermore, in
other embodiments, the brake calipers 102 and the brake discs 104 may be
replaced by other types of brake assemblies, such as drum brakes,
electromagnetic
brakes, and the like.
[0079] An operator may control actuation of the brake calipers 102. For
example,
the handles 34 on the tiltable conveyor section 28 may include a brake release
button 106 (shown in FIG. 6). Pressing the brake release button 106 disengages
the
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brake calipers 102 to allow pivotal movement of the slewing conveyor section.
Letting go of the brake release button 106 engages the brake calipers 102 to
inhibit
further movement. In other embodiments, the brake release button 106 may be
replaced by another brake release control, such as a laser sensor, pressure
sensor,
proximity sensor, and the like.
[0080] The slewing conveyor section 26 also includes two spaced apart conveyor
side frames 110 attached to the top surface of the base 100 using bolts,
screws or
another fastener. The side frames 110 generally support components for
providing
the conveying surface 42, including a driven roller 112, an idler roller 114,
a belt 116
reeved around the rollers 112 and 114, and a conveyor motor 118 for rotating
the
driven roller 112 and the belt 116.
[0081] The two rollers 112 and 114 are rotatably supported and spaced
apart by
the side frames 110. In particular, the rear of the side frames 110 have
grooves (not
shown) for receiving the ends of the driven roller 112, and the front of the
side
frames 110 have apertures for receiving the ends of the idler roller 114. The
right
end of the driven roller (as viewed in FIG. 5) protrudes beyond the right side
frame
110, through a shaft bearing 120, and is coupled to the motor 118 so that
rotation of
the motor 118 also rotates the driven roller 112. The shaft bearing 120 is
also
fastened to the right side frame 110 to partially support the driven roller
112. There is
also a corresponding shaft bearing (not shown) on the other end of the driven
roller
112.
[0082] The right side frame 110 also supports the conveyor motor 118. In
particular, the motor 118 has an arm 122 with an aperture 123 therein that
receives
a bolt 124 extending outward from the right side frame 110. Furthermore, the
housing of the shaft bearing 120 also partially supports the motor 118.
[0083] As described above, the belt 116 is reeved around the rollers 112
and 114
such that the belt 116 rotates when the motor 118 drives the driven roller
112. A
tensioner roller 125 may be located between the rollers 112 and 114 for
providing
tension to the belt 116 and to prevent slippage. The side frames 110 support
the
tensioner roller 125 in a similar way as the idler roller 114.
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[0084] The slewing conveyor section 26 also includes a rear bracket 130
attached to the base 100 and extending upward therefrom for coupling the
flexible
conveyor 30 to the slewing conveyor section 26, and two side posts 132
attached to
the sides of the base 100 and extending upward therefrom. Two pillow block
bearings 134 are fastened to the front faces of the posts 132 for pivotally
coupling
the tiltable conveyor section 28 to the slewing conveyor section 26 about the
horizontal axis H.
[0085] A sub-frame 140 is attached to the left side post 132 (as viewed
in FIG. 5).
The sub-frame 140 supports a brake caliper 142 for locking the tiltable
conveyor
section 28 in a particular angular position relative to the slewing conveyor
section
26, and a counter balance mechanism 144 for counterbalancing the tiltable
conveyor
section 28 about the horizontal axis H, as will be described below.
[0086] Referring now to FIG. 6, the tiltable conveyor section 28
includes a
support frame 150 for attaching the tiltable conveyor section 28 to the
slewing
conveyor section 26 and for supporting other components of the tiltable
section. The
support frame 150 includes a base portion 152 and two spaced apart support
members 154 extending upward and rearward from the base portion 152 (as viewed
in FIG. 6).
[0087] The rearward ends of the support members 154 have brackets 156 and
157. The first bracket 156 includes two spaced apart plates on opposing sides
of the
right support member 154 (as viewed in FIG. 6). The second support bracket 157
includes a circular casing with a rectangular cutout for receiving the end of
a motor
168. Both brackets 156 and 157 have aligned apertures 158 therein for
receiving
respective pins (not shown), which extend through the pillow block bearings
134 of
the slewing conveyor section 26 (shown in FIG. 5) so as to pivotally couple
the
tiltable conveyor section 28 to the slewing conveyor section 26 about the
horizontal
axis H. The apertures 158, pins and pillow block bearings 134 generally define
the
horizontal axis H.
[0088] Referring to FIGS. 5 and 6, the circular casing of the second
bracket 157
mates with a corresponding casing 159 on the right side post 132 of the
slewing
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conveyor section 26 (as viewed in FIG. 6). These circular casings tend to help
conceal and protect the pins.
[0089] Two side frames 160 are attached to base 152 for supporting components
that provide the conveying surface 40, which includes a driven roller 162, an
idler
roller 164, a belt 166 reeved around the rollers 162 and 164, and a motor 168
for
rotating the driven roller 162 and the belt 166. The rollers 162 and 164, the
belt 166,
and the motor 168 are generally similar to the rollers 112 and 114, and the
belt 116
and the motor 118 of the slewing conveyor section 26 and are assembled in a
similar fashion. One difference is that the conveying surface 40 includes
three
tension rollers 170 for tensioning the belt 166.
[0090] The free end 32 of the tiltable conveyor section 28 includes a
lip plate 171
slightly spaced apart from the end of the belt 166. A panel 172 attached to
the
underside of the side frames 160 supports the lip plate 171. The lip plate 171
may
be made from Ultra-High Molecular Weight Polyethylene (UHMW), or other
suitable
materials such as metal or other plastics.
[0091] Referring to FIGS. 5 and 6, and as previously described, the sub-
frame
140 of the slewing conveyor section 26 includes a brake caliper 142 and a
counter
balance mechanism 144 for controlling movement of the tiltable conveyor
section 28.
[0092] The brake caliper 142 (shown in FIG. 5) releasably engages a
brake disc
180 (shown in FIG. 6) attached to the end of the right support member 154 (as
viewed in FIG. 6) and is located on the outside surface thereof. When the
brake
caliper 142 disengages the brake disc 180, the tiltable conveyor section 28
can pivot
up and down about the horizontal axis H. When the tiltable conveyor section 28
has
been pivoted to a desired position, the brake caliper 142 frictionally engages
the
brake disc 180 so as to inhibit further movement. The brake release button 106
located on the handle 34 may control operation of the brake caliper 142. In
other
embodiments, the brake release button 106 may be replaced by another brake
release control, such as a laser sensor, pressure sensor, proximity sensor,
and the
like.
[0093] The brake caliper 142 and brake disc 180 are generally similar to
the
brake calipers 102 and brake discs 104. One difference is that the brake
caliper 142
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includes linkages 182 for amplifying the force of the brake caliper 142 so as
to
increase the frictional force between the calipers and the brake disc 180.
This
increased frictional force helps support the weight of the tiltable conveyor
section 28
in addition to inhibiting movement thereof. The brake calipers 102 do not
include the
linkages 182, because the brake calipers 102 inhibit movement of the slewing
conveyor section 26, but do not significantly support the weight of the
slewing
conveyor section 26.
[0094] In other embodiments, the brake caliper 142 and brake disc 180
may be
replaced by other types of brake assemblies, such as drum brakes,
electromagnetic
brakes, and the like.
[0095] In the illustrated embodiment, the counter balance mechanism 144
comprises an air cylinder 145 (shown in FIGS. 2 and 5) pivotally coupled to
the sub-
frame 140 and the tiltable conveyor section 28. The air cylinder 145 generally
applies a force that counter-balances the weight of the tiltable conveyor
section 28
so that the tiltable conveyor section 28 feels almost weightless when pivoting
the
tiltable conveyor section 28 up and down about the horizontal axis H.
[0096] The air cylinder 145 includes a casing pivotally coupled to the
sub-frame
140 through a cylinder mount 146 (shown in FIG. 5), and a rod (not shown)
telescopically mounted within the casing and having a distal end pivotally
coupled to
a pair of extension brackets 184 (shown in FIG. 6) extending rearward from the
end
of the right support member 154 (as viewed in FIG. 6). The extension brackets
184
have apertures 186 for receiving a pin (not shown) so as to pivotally couple
the rod
of the air cylinder 145 to the tiltable conveyor section 28.
[0097] In use, the tiltable conveyor section 28 has a weight that
creates a first
moment of force about the horizontal axis H, and the rod of the counter
balance
mechanism 144 applies a downward force on the extension brackets 184, which
creates a second moment of force about the horizontal axis H that is
approximately
equal and opposite to the first moment of force. As such, the second moment of
force created by the air cylinder 145 counteracts the first moment of force
created by
the weight of the tiltable conveyor section 28 such that an operator can apply
a small
force at the handles 34 in order to pivot the tiltable conveyor section 28 up
or down.
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[0098] In the illustrated embodiment, the air cylinder 145 applies a
predetermined
amount of pressure to the extension brackets 184. As such, when the tiltable
conveyor section 28 pivots up or down, the rod of the air cylinder 145 extends
and
retracts and the amount of air within the cylinder will increase or decrease
to
maintain pressure within a predetermined range. For example, when the tiltable
conveyor section 28 pivots upward, the rod extends downward and more air
enters
the cylinder casing so as to maintain pressure with the predetermined range.
When
the tiltable conveyor section 28 pivots downward, the rod retracts upwards and
air
exits the cylinder casing so as to maintain pressure with the predetermined
range. In
other embodiments, counter balance mechanism 144 may have different
configurations, such as a solid mass selected to counter-balance the weight of
the
tiltable conveyor section 28.
[0099] Referring now to FIG. 7, the flexible conveyor 30 includes an
entry section
30a, a flexible section 30b, and an exit section 30c. The entry section 30a is
located
at the first end 60 of the flexible conveyor 30, and the exit section 30c is
located at
the second end 62. The flexible section 30b is located between the entry
section 30a
and the exit section 30c.
[0100] The entry section 30a includes a pair of triangular brackets 190
for
pivotally connecting the flexible conveyor 30 to the slewing conveyor section
26
along the axis F. In particular, the triangular brackets 190 have aligned
apertures
192 for receiving corresponding pins or bolts 194 (shown in FIG. 5) that
extend
laterally outward from the rear bracket 130 of the slewing conveyor section
26. Two
spaced apart rollers 196 are also interposed between the triangular brackets
190
and are rotatably coupled thereto for conveying packages along the entry
section
30a.
[0101] The flexible section 30b includes a pair of side frames 200
spaced apart
from each other and coupled to the entry section 30a and to the exit section
30c.
Each side frame 200 includes a plurality of pivotally interconnected and criss-
crossing links 202 (also shown in FIGS. 8-12). The links 202 can pivot
relative to
each other, which allows each side frame 200 to expand and contract
independently
of the other side frame 200.
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[0102] Rollers 204 are interposed between the side frames 200 and are
configured to convey objects from the slewing conveyor section 26 toward the
extendable conveyor 16. Each roller 204 includes a shaft 206 rotatably coupled
to an
opposing pair of links 202 on the side frames 200. For example, the shaft 206a
of
one roller 204a is coupled to an opposing pair of links 202a of the side
frames 200.
[0103] In use, when one or both of the side frames 200 expand or
retract, the
axis of each shaft 206 shifts or tilts corresponding to the expansion or
retraction of
the side frames 200. More particularly, if both side frames 200 expand, the
shafts
206 will shift away from each other so as to lengthen the flexible conveyor
30. If both
side frames 200 retract, the shafts 206 will shift closer together so as to
shorten the
flexible conveyor 30. If only one side frame 200 expands, the shafts 206 will
tilt
relative to each other so as to curve the flexible conveyor 30. If different
portions of
each side frame 200 expand and contract independently of each other, the
flexible
conveyor 30 may curve in two directions so as to form an S-shape (e.g. as
shown in
FIG. 3).
[0104] It will be appreciated that the side frames 200 are also capable
of
expanding and retracting in a vertical direction so as to incline or decline
the flexible
conveyor 30, for example, to gravity feed packages along the flexible conveyor
30.
[0105] In the illustrated embodiment, the rollers 204 are skate rollers
such that
each shaft 206 supports a plurality of skate wheels 207. The wheels 207 of
each
roller 204 are spaced apart along each shaft 206 and are axially offset from
the
wheels 207 of adjacent rollers 204 so that the wheels 207 of one roller 204
mesh
with the wheels 207 of an adjacent roller 204. Meshing the wheels 207 helps
maintain a continuous conveying surface, particularly when the flexible
conveyor 30
expands or curves, which would otherwise create spaces between the rollers
204.
[0106] The exit section 30c includes a declining roller assembly 198,
which
conveys packages from flexible section 30b to the extendable conveyor 16. The
roller assembly 198 includes two spaced apart side plates 210 that are
interconnected by cross members 211, and six rollers 212 interposed between
the
side plates 210 and rotatably coupled thereto. The rollers 212 are arranged in
a
declining fashion from front to rear such that packages travel to the
extendable
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conveyor 16 under the force of gravity. In some embodiments, one or more of
the
rollers 212 may be motorized.
[0107] The side plates 210 of the roller assembly 198 are pivotally
coupled to the
shaft 206c of the last roller 204c such that the roller assembly 198 can pivot
up and
down relative to the flexible section 30b, for example, when the angle between
the
flexible conveyor 30 and the extendable conveyor 16 changes as shown in FIGS.
8
and 9.
[0108] The roller assembly 198 includes a first set of three support
rollers 214
that support the roller assembly 198 on the extendable conveyor 16. The
flexible
conveyor 30 also includes a second set of support rollers 216 rotatably
coupled to a
pair of links 218 of the side frames 200. Each link 218 is pivotally coupled
to a
corresponding armature 219, which is in turn pivotally coupled to the side
plates 210
of the roller assembly 198. Accordingly, the second support rollers 216 shift
positions either when the side frames 200 expand or retract, or when the
roller
assembly 198 pivots up or down about the last shaft 206c.
[0109] Two removable anchor bars 220 are also coupled to the flexible
conveyor
30. Each anchor bar 220 has one end pivotally coupled to a corresponding link
218,
and an opposing end that can be pivotally coupled to the frame 22 along an
axis T.
In particular, referring to FIG. 4, the opposing end of each anchor bar 220 is
pivotally
coupled to a corresponding one of two brackets 222 extending rearward from the
lift
frame 80. As shown in FIGS. 8 and 9, the anchor bars 220 are installed after
expanding the side frames 200 and lengthening the flexible conveyor 30. The
anchor
bars 220 provide a fixed length between the slewing conveyor section 26 and
the
second end 62 of the flexible conveyor 30.
[0110] The anchor bars 220 anchor the roller assembly 198 relative to the
frame
22 and maintain lateral alignment of the second end 62 of the flexible
conveyor 30
with the extendable conveyor 16. In particular, referring again to FIG. 3,
when the
slewing conveyor section 26 pivots from side-to-side, the flexible conveyor 30
tends
to form an S-shape such that the first end 60 of the flexible conveyor 30
remains
aligned with the slewing conveyor section 26, while the second end 62 remains
aligned with the extendable conveyor 16. The anchor bars 220 (not shown in
FIG. 3)
CA 02854306 2014-06-13
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constrain the lateral position of the second end 62 of the flexible conveyor
30 such
that the second transverse axis 63 remains generally perpendicular to the
second
fixed longitudinal axis 56. At the same time, the anchor bars 220 allow the
first end
60 of the flexible conveyor 30 to pivot from side-to-side with the slewing
conveyor
section 26, and the first end 60 is not constrained in a lateral position by
the anchor
bars 220. As such, the first end 60 of the flexible conveyor 30 can remain
aligned
with the slewing conveyor section 26 (i.e. such that the first transverse axis
61
remains generally perpendicular to the first pivoting longitudinal axis 54).
Without the
anchor bars 220, the entire flexible conveyor 30 might tend to pivot with the
slewing
conveyor section 26 resulting in misalignment between the second end 62 of the
flexible conveyor 30 and the extendable conveyor 16.
[0111] While the anchor bars 220 constrain the lateral position of the
second end
62 and inhibit side-to-side movement of the roller assembly 198, the anchor
bars
220 still permit the flexible conveyor 30 to pivot up and down relative to the
slewing
conveyor section 26, for example, as shown in FIGS. 8 and 9.
[0112] The anchor bars 220 may be removed, for example, when the conveyor
apparatus 20 is not in use. Removing the anchor bars 220 allows the flexible
conveyor 30 to be collapsed into a smaller structure as shown in FIG. 7, for
example, to store the flexible conveyor 30.
[0113] In some embodiments, the anchor bars 220 may be replaced by, or used
in conjunction with, other devices for maintaining the second end 62 of the
flexible
conveyor 30 in alignment with the extendable conveyor 16. For example, the
roller
assembly 198 may include a pair of brackets for physically securing the second
end
62 of the flexible conveyor 30 to the extendable conveyor 16.
[0114] Referring to FIGS. 8-12, operation of the conveyor apparatus 20 will
now
be described.
[0115] As shown in FIG. 8, the conveyor apparatus 20 is positioned on a
loading
dock 300, and in particular, on a dock leveler 302, in preparation for
unloading a
truck trailer 304. The first section 18a of the extendable conveyor 16 is
coupled to
the frame 22 of the conveyor apparatus 20 using the link bar assembly 94.
Furthermore, the roller assembly 198 of the flexible conveyor 30 is pivoted
upwards
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while resting on an inclined conveyor 19, which is part of a facility conveyor
system.
The inclined conveyor 19 generally transports packages from the extendable
conveyor 16 to other areas within the facility, which may be a distribution
center.
[0116] As shown in FIG. 9, the dock leveler 302 has been tilted upward
and a lip
plate 306 of the dock leveler 302 rests on the floor of the truck trailer 304
as known
to a person skilled in the art. The extendable conveyor 16 has been extended
forward so as to advance the conveyor apparatus 20 into the truck trailer 304.
[0117] While the conveyor apparatus 20 moves upward along the dock leveler
302, the frame 22 pivots upward relative to the extendable conveyor 16, which
changes the angular position of the link bar assembly 94. The change in height
of
the conveyor apparatus 20 also causes the flexible conveyor 30 to pivot
downward
relative to the frame 22. The anchor bars 220 generally follow the pivoting
motion of
the flexible conveyor 30. At the same time, the roller assembly 198 pivots
upward
relative to the rest of the flexible conveyor 30 while remaining on the
inclined
conveyor 19.
[0118] FIG. 9 also shows the roller assembly 198 supported by the second
set of
support rollers 216 while the roller assembly 198 moves from the inclined
conveyor
19 to the extendable conveyor 16. Without the second support rollers 216, the
roller
assembly 198 might jam into the extendable conveyor 16 during the transition.
[0119] The conveyor apparatus 20 allows an operator to unload a first row
of
stacked packages near the opening of the truck trailer 304. This is typically
a design
challenge because of various problems including space constraints, the slope
of the
dock leveler 302, and truck trailers having different elevations. The conveyor
apparatus 20 overcomes one or more of these problems by providing an operator
platform 74 that positions the operator at a user adjustable height for
unloading
packages at the entrance of the trailer, a pivoting conveyor 24 with an
adjustable
height so as to fit within the entrance of the truck trailer 304, and a
flexible conveyor
that is pivotally coupled to the slewing section 26 to accommodate truck
trailers of
different elevations and dock levelers of different slopes. The flexible
conveyor 30
30 also includes a roller assembly 198 that pivots up and down relative to
the flexible
section 30b through the cooperation of the second support rollers 216, links
218,
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and armatures 219 (all shown in FIG. 7). Pivotally coupling the roller
assembly 198
to the flexible section 30b allows the roller assembly 198 to remain flat on
the
extendable conveyor 16 while the pivoting conveyor 24 moves up and down,
and/or
while the flexible conveyor 30 pivots up and down relative to the slewing
section 26.
[0120] As shown in FIG. 10, the conveyor apparatus 20 is now entering the
truck
trailer 304 and is level on the floor of the truck trailer 304. As a result,
the frame 22
has risen relative to the extendable conveyor 16 thereby pivoting the link bar
assembly 94 downward relative to the frame 22.
[0121] The pivoting conveyor 24 has also been lowered relative to the
frame 22
using the conveyor lifting mechanism 85. It is generally advisable to lower
the
pivoting conveyor 24 while entering the truck trailer 304 in order to provide
more
clearance between the top of the slewing conveyor section 26 and the ceiling
of the
truck trailer 304.
[0122] The pivoting conveyor 24 has also been lowered such that the free end
32
of the tiltable conveyor section 28 is adjacent to the operator platform 74.
In this
position, an operator can stand on the operator plafform 74 while moving
packages
from the truck trailer floor and onto the free end 32 of the tiltable conveyor
section
28. The operator can also swing the free end 32 from side-to-side (e.g. as
shown in
FIG. 3) about the vertical axis V, or up and down about the horizontal axis H,
by
grasping one of the handles 34 and depressing the brake release button 106 so
as
to release the brake calipers 102 and 142. Once in a desired position, the
operator
lets go of the brake release button 106 and the brake calipers 102 and 142
lock the
slewing conveyor section 26 and the tiltable conveyor section 28 in place and
inhibit
further movement. Moving and locking the free end 32 in different positions
allows
the operator to unload packages located in various lateral and vertical
positions
within the truck trailer 304.
[0123] In other embodiments, the brake release button 106 may be
replaced by
another brake release control, such as a laser sensor, pressure sensor,
proximity
sensor, and the like. In such embodiments, the operator releases the brake
calipers
102 and 142 by activating the brake release control, for example, by placing
their
hand on one of the handles 34.
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[0124] In FIG. 10, it can also be seen that the roller assembly 198 is
supported by
the first support rollers 214 now instead of the second support rollers 216 as
in FIG.
9. Without the first support rollers 214, the roller assembly 198 might drag
on the
inclined conveyor 19.
[0125] As shown in FIG. 11, the operator platform 74 has risen by actuating
the
platform elevation mechanism 75. Raising the operator platform 74 may help
position the operator at a more ergonomic height for unloading packages, such
as
packages stacked at a height midway within the truck trailer 304, or higher.
Raising
the operator platform 74 may help reduce physical strains that the operator
might
otherwise experience while reaching for packages near the ceiling of the truck
trailer.
[0126] The pivoting conveyor 24 has also been raised using the conveyor
lifting
mechanism 85. Raising the pivoting conveyor 24 may help provide a steeper
downward slope for gravity feeding packages from the slewing conveyor section
26
to the extendable conveyor 16. It will be appreciated that the pivoting
conveyor 24 is
near the maximum height in this position while still maintaining an
appropriate
clearance between the slewing conveyor section 26 and the ceiling of the truck
trailer 304.
[0127] As shown in FIG. 12, the tiltable conveyor section 28 has been
pivoted
upward about the horizontal axis H, which may help the operator ergonomically
unload packages stacked midway or higher within the truck trailer 304.
[0128] While pivoting the tiltable conveyor section 28 up or down, the
counter
balance mechanism 144 applies a force that makes the tiltable conveyor section
28
feel near weightless to provide a "floating operation". More particularly, the
counter
balance mechanism 144 applies a moment of force about the horizontal axis H,
which counteracts a corresponding opposite moment of force caused by the
weight
of the tiltable conveyor section 28. If the counter balance mechanism 144 is
configured such that the two moments of force are approximately equal, the
operator
can move the tiltable conveyor section 28 up or down by pulling on the handles
34
with a relatively small amount of force.
[0129] Once the free end 32 has been moved to a desired location, for
example
by pivoting the tiltable conveyor section 28 up and down, and/or by pivoting
the
CA 02854306 2014-06-13
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slewing conveyor section 26 from side to side, the operator may begin
unloading
one or more packages from the shipping container and onto the conveyor
apparatus
20. In particular, the operator picks up, or slides, a package from the truck
trailer 304
and onto the free end 32. The conveying surface 40 then conveys the package
along the tiltable conveyor section 28 and to the slewing conveyor section 26,
where
the package transitions onto the conveying surface 42. The conveying surface
42
carries the package horizontally along the slewing conveyor section 26 and to
the
first end 60 of the flexible conveyor 30. If the slewing conveyor section 26
has been
pivoted to one side, the package will gradually curve along a continuous path
and
down the S-shaped flexible conveyor 30 under the force of gravity. Otherwise,
if the
slewing conveyor section 26 has not been pivoted, the package will travel
straight
down the flexible conveyor 30. In both cases, the package exits the conveyor
apparatus 20 onto the extendable conveyor 16.
[0130] The process of successively advancing the conveyor apparatus 20
into
the truck trailer 304, adjusting the height of the operator platform 74 and/or
the
slewing conveyor section 26, moving the free end 32 up and down or side-to-
side,
and unloading packages from the truck trailer 304, continues until all
packages have
been unloaded. After unloading the truck trailer 304, the conveyor apparatus
20 may
be removed from the truck trailer 304 by retracting the extendable conveyor
16.
[0131] While the conveyor apparatus 20 herein has been described with
respect
to unloading packages from truck trailers, the conveyor apparatus 20 may also
be
used to unload other objects from other shipping containers, such as packages
within intermodal containers transported by cargo ships, railcars, and
transport
trucks. Furthermore, the conveyor apparatus 20 may be used to unload mailbags
from mail trucks and other bagged products from shipping containers. The
conveyor
apparatus 20 may also be used to load and unload packages at other locations
other
than shipping containers, for example, on the floor of a warehouse or
distribution
center.
[0132] The conveyor apparatus 20 can also be moved between two or more
loading bays so as to unload truck trailers at different loading bays. For
example, the
extendable conveyor 16 might be mounted on transversely extending rails within
the
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floor of the distribution center, thereby allowing the extendable conveyor 16
to move
laterally along the rails from one loading bay to another. The conveyor
apparatus 20
generally moves laterally with the extendable conveyor 16 to each loading bay.
In
particular, the caster wheels 72 can swivel to a lateral orientation while the
conveyor
apparatus 20 moves laterally with the extendable conveyor 16 to each loading
bay.
Once at a specific loading bay, the caster wheels 72 can swivel back to a
longitudinal orientation and the extendable conveyor 16 can extend and push
the
conveyor apparatus 20 into the truck trailer as described previously.
Generally, the
link bar assembly 94 couples the frame 22 to the extendable conveyor 16 with
sufficient strength and stability so as to allow the conveyor apparatus 20 to
travel
laterally with the extendable conveyor 16.
[0133] Furthermore, the conveyor apparatus 20 may also be used to load
packages into a truck trailer or another shipping container. In this case, the
flexible
conveyor 30 may be powered, and the conveying surfaces 40 and 42 may be
operated in reverse, so as to convey packages from the extendable conveyor 16
toward the free end 32 where an operator loads the packages into the truck
trailer.
[0134] Referring now to FIG 13, illustrated therein is a conveyor
apparatus 420
made in accordance with an embodiment of the present invention. The conveyor
apparatus 420 is similar in many respects to the conveyor apparatus 20 and
similar
elements are given similar reference numerals incremented by four hundred. In
particular, the conveyor apparatus includes a frame 422 connectable to the
extendable conveyor 16, a pivoting conveyor 424 pivotally coupled to the frame
422
for unloading packages from a shipping container, and a flexible conveyor 430
extending from the pivoting conveyor 424 toward the extendable conveyor 16 for
conveying packages from the pivoting conveyor 424 to the extendable conveyor
16.
Furthermore, the pivoting conveyor 424 includes two conveyor sections, namely,
a
generally horizontal slewing conveyor section 426 pivotally coupled to the
frame 422
for pivotal movement about a vertical axis, and a tiltable conveyor section
428
having a proximal end pivotally coupled to the slewing conveyor section 26 for
pivotal movement about a horizontal axis.
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[0135] One difference is that the frame 422 includes a base supported by
two
motorized wheels 473 for driving the frame 422. As such, the conveyor
apparatus 20
can move in and out of the shipping container under its own power. In
contrast, the
conveyor apparatus 20 described previously generally relies on the extendable
conveyor 16 to push it in and out of the shipping container.
[0136] In the illustrated embodiment, two motorized wheels 473 are
located at the
front of the frame 422 and two caster wheels 472 are located at the rear of
the frame
422. As such, the conveyor apparatus 20 operates as a front wheel drive
vehicle
with skid steering capabilities. For example, when turning the conveyor
apparatus
20, one motorized wheel 473 rotates faster than the other motorized wheel 473,
and
the caster wheels 472 swivel freely in response to movement of the conveyor
apparatus 20. The motorized wheels 473 may also be rotated in opposite
directions
to provide a tighter turning radius.
[0137] In other embodiments, the wheels 472 and 473 may have other
configurations and the conveyor apparatus 20 may be driven in other modes. For
example, two caster wheels 472 may be located at the front of the frame 422
and
two motorized wheels 473 may be located at the rear of the frame 422 so as to
provide rear wheel drive. Furthermore, all of the wheels may be motorized
wheels
473.
[0138] The motorized wheels 473 are generally powered by electrical motors
(not
shown). In other embodiments, the motorized wheels 473 may be powered by any
other suitable power source such as pneumatics, hydraulics and the like.
[0139] Referring now to FIGS. 14-20, illustrated therein is a conveyor
apparatus
520 made in accordance with another embodiment of the present invention. In
FIG.
14, the conveyor apparatus 520 is configured to load packages into a shipping
container. However, the conveyor apparatus 520 can also be configured to
unload
packages from the shipping container as will be described with respect to FIG.
20.
[0140] The conveyor apparatus 520 is similar in some respects to the
conveyor
apparatus 20 and similar elements are given similar reference numerals
incremented by five hundred. For example, the conveyor apparatus includes a
frame
522 connectable to an extendable conveyor 516. As shown in FIGS. 14 and 15,
the
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. .
extendable conveyor 516 may be a powered flexible conveyor, which may include
powered skate wheels or powered rollers. Alternatively, the frame 522 could be
connected to another type of extendable conveyor such as a telescoping
extendable
conveyor, which may be similar to the extendable conveyor 16 described
previously.
[0141] With reference to FIG. 14, the conveyor apparatus 520 includes a
pivoting
conveyor 524. More specifically, as shown in the illustrated embodiment, the
pivoting
conveyor 524 includes three conveyor sections, namely, a first pivotable
conveyor
section 525, a second non-pivotable conveyor section 526, and a third tiltable
conveyor section 527. Each conveyor section 525, 526, 527 includes a
respective
conveying surface 540, 541, 542 for conveying objects thereon. As shown, the
conveying surfaces 540, 541, 542 may be conveyor belts, which may be powered
by
motors.
[0142] Similar to the apparatus 20 described above, the pivoting
conveyor 524 is
pivotally coupled to the frame 522 for pivotal movement about a vertical axis
V and
for pivotal movement about a first horizontal axis H1. However, one difference
is that
the first pivotable conveyor section 525 is pivotally coupled to the frame 522
for
pivotal movement about both the vertical axis V and the first horizontal axis
H1, as
opposed to having a slewing conveyor section and a separate tiltable conveyor
section.
[0143] The first pivotable conveyor section 525 conveys objects between a
free
end 532 and the second non-pivotable conveyor section 526. The free end 532 is
generally configured to support objects being loaded or unloaded from a
shipping
container. Furthermore, the free end 532 can be moved up and down, and side-to-
side by pivoting the first pivotable conveyor section 525 about the first
horizontal axis
H2 and the vertical axis V.
[0144] The second non-pivotable conveyor section 526 conveys objects between
the first pivotable conveyor section 525 and the third tiltable conveyor
section 527.
The second non-pivotable conveyor section 526 maintains a generally horizontal
orientation (e.g. such that the second conveying surface 541 remains in a
generally
horizontal plane).
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[0145] The third tiltable conveyor section 527 conveys objects between
the
second non-pivotable conveyor section 526 and the extendable conveyor 516. The
third tiltable conveyor section 527 includes a rear end 533 pivotally coupled
to the
extendable conveyor 516. Furthermore, the third tiltable conveyor section 527
is
pivotally coupled to the frame 522 for pivotal movement about a second
horizontal
axis H2. Pivoting the third tiltable conveyor section 527 about the second
horizontal
axis H2 allows the rear end 533 to be moved up and down, for example, to
remain at
the same general height as the extendable conveyor 516.
[0146] Referring now to FIG. 16, the apparatus 520 may include a support
arm
550 for pivotally coupling the first pivotable conveyor section 525 to the
frame 522
about the vertical axis V. In some examples, the support arm 550 may be
pivotally
coupled to the frame 522 so that the vertical axis V is located near the
transition
between the first and the second conveyor sections 525, 526. For example, as
shown in FIGS. 15 and 16, the support arm 550 extends longitudinally from the
first
pivotable conveyor section 525 towards the second non-pivotable conveyor
section
526 underneath the first and second conveying surfaces 540, 542. The support
arm
550 is pivotally coupled to the frame 522 about the vertical axis V at a
location
underneath the transition between the first and second conveying surfaces 540,
542.
In some examples, the support arm 550 may be pivotally coupled to the frame
522
using a slewing bearing 582, which may be similar to the slewing bearing 82
described previously.
[0147] With reference to FIG. 16, the first pivotable conveyor section
525 is also
pivotally coupled to the support arm 550 about the first horizontal axis I-11.
For
example, the first pivotable conveyor section 525 may include a cross-member
552
having two opposing mounting brackets 554 for pivotally coupling the first
pivotable
conveyor section 525 to two opposing upright posts 556 on the support arm 550.
[0148] Pivotal movement of the first pivotable conveyor section 525
about the
vertical axis V and horizontal axis H may be controlled in a similar way as
the
apparatus 20. For example, with reference to FIGS. 15 and 16, the apparatus
520
may include a counter balance mechanism 644, which may be similar to the
counter
balance mechanism 144. As shown in FIG. 15, the counter balance mechanism 644
CA 02854306 2014-06-13
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may be mounted underneath the second non-pivotable conveyor section 526, and
may include an air cylinder 645 pivotally coupled to the first pivotable
conveyor
section 525 through a link arm 648 that is rigidly attached to the cross-
member 552.
In use, the air cylinder 645 applies a force to the link arm 648, which can be
selected
to counteract the weight of the first pivotable conveyor section 525 about the
first
horizontal axis H1. This may allow the first pivotable conveyor section 525 to
feel
almost weightless when being pivoted up and down. For example, an operator can
apply a small force at handles 534 in order to pivot the first pivotable
conveyor
section 525 up or down.
[0149] The apparatus 520 may also include one or more brake assemblies for
inhibiting movement of the first pivotable conveyor section 525 about the
vertical
axis V and/or the first horizontal axis H1. The brake assemblies may be
similar to the
ones described above and may include brake discs and calipers, which may be
activated and deactivated by a brake release button or sensor on the handles
534.
[0150] The apparatus 520 includes one or more transition plates located
between
the first and second conveying surfaces 540, 541 for transferring objects
therebetween. For example, as shown in FIG. 16, there is a first transition
plate 560
and a second transition plate 562. The first transition plate 560 is located
adjacent to
the first pivotable conveyor section 525, and the second transition plate 562
is
located adjacent to the second non-pivotable conveyor section 526.
[0151] One of the transition plates 560, 562 overlaps the other. For
example, in
the illustrated embodiment, the second transition plate 562 overlaps the first
transition plate 560. This may reduce the likelihood of objects jamming on the
transition plates 560, 562 when loading objects into a shipping container. In
other
embodiments, the overlap of the transition plates 560, 562 may be reversed,
for
example, when unloading objects from a shipping container.
[0152] In some examples one or more of the transition plates 560, 562
may be
configured to move. For example, with reference to FIGS. 17A-17C, the first
transition plate 560 is configured to move laterally from side-to-side
relative to the
first conveying surface 540 and may be referred to as a "shuttling transition
plate". In
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contrast, the second transition plate 562 may remain stationary and may be
referred
to as a "fixed transition plate".
[0153] Movement of the shuttling transition plate 560 generally occurs
in
response to pivoting the first pivotable conveyor section 525 from side-to-
side about
the vertical axis V. For example, with reference to FIG. 17A, when the first
pivotable
conveyor section 525 pivots clockwise, the shuttling transition plate 560 may
move
to the right by a distance D1 (as viewed from the free end 532 in FIG. 17A).
Similarly, as shown in FIG. 17C, when the first pivotable conveyor section 525
pivots
counter-clockwise, the shuttling transition plate 560 may move to the left by
a
distance D2 (as viewed from the free end 532 in FIG. 17C).
[0154] In some embodiments, the distances D1 and D2 may depend upon the
angular rotation of the first pivotable conveyor section 525 about the
vertical axis V.
For example, the distances D1 and D2 may be about 4-centimeters when the first
pivotable conveyor section 525 is pivoted about the vertical axis by about 20-
degrees. In other examples, the distances D1 and D2 could be larger or
smaller.
[0155] Referring now to FIG. 16, movement of the shuttling transition
plate 560
may be controlled automatically using a shuttling mechanism. For example, in
the
illustrated embodiment, the shuttling transition plate 560 is slidably mounted
on a
support plate 564, which is fastened to the top of the support arm 550. In
particular,
a guide bar 566 is fastened to the bottom of the shuttling transition plate
560 and
extends downward through a lateral guide slot 568 in the support plate 564.
This
allows the shuttling transition plate 560 to move from side-to-side relative
to the
support plate 564 and the rest of the first pivotable conveyor section 525.
Motion
along the guide slot 568 is controlled using a pin 580 fastened to the bottom
of the
fixed transition plate 562. The pin 580 extends downward through a
longitudinal slot
582 in the shuttling transition plate 560, and through a curved slot 584 in
the support
plate 564. In operation, when the first pivotable conveyor section 525 pivots
from
side-to-side, the pin 580 moves within the curved slot 584 while also pressing
again
the edges of the longitudinal slot 582 on the shuttling transition plate 660.
This
causes the shuttling transition plate 560 to move sideways along the lateral
guide
CA 02854306 2014-06-13
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,
slot 568. In other examples, movement of the shuttling transition plate 560
may be
controlled in other ways, for example, using motors or other actuators.
[0156] In general, movement of the shuttling transition plate 560 can
help reduce
gaps between the conveying surfaces 540, 541 that might otherwise cause
objects
to jam.
[0157] The conveyor apparatus 520 may also have other features that
facilitate
transfer of objects between the conveying surfaces 540, 541, 542. For example,
the
second conveying surface 541 may have a lower coefficient of friction than the
first
conveying surface 540. More particularly, the first and third conveying
surfaces 540,
542 may be made from Ethylene Propylene Diene Monomer Rubber (EDPM
Rubber) and the second conveying surface 541 may be made from Acetal (also
known as polyoxymethylene). The low friction of the second conveying surface
541
may allow objects to slip and change directions more easily while
transitioning
between the first and second conveying surfaces 540, 541. This can help reduce
the
likelihood of objects jamming through the transition.
[0158] Referring again to FIG. 14, the apparatus 520 may include one
or more
side guides extending along the sides of the conveying surfaces 540, 541, 542
for
guiding the objects thereon. For example, as shown, there may be first and
second
pivoting side guides 590, 592 positioned on each side of the second conveying
surface 541. The first and second pivoting side guide 590, 592 may be
telescopically
mounted to each other. Furthermore, the first pivoting side guide 590 may be
pivotally coupled to the first pivotable conveyor section 525, and the second
pivoting
side guide 592 may be pivotally coupled to the second non-pivotable conveyor
section 526. Thus, when the first pivotable conveyor section 525 pivots from
side-to-
side about the vertical axis V, the first and second pivoting side guides 590,
592 also
pivot and telescope with respect to each other, which can help guide objects
through
the transition between the first and second conveying surfaces 540, 541.
[0159] The apparatus 520 may also include one or more fixed side
guides. For
example, fixed side guides 594 may be rigidly mounted to the third tiltable
conveyor
section 527 along the third conveying surface 542.
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[0160] In the illustrated embodiment, the apparatus 520 includes an
operator
platform 574, which may be similar to the operator platform 74 described
above. The
apparatus 520 may also include a platform elevation mechanism 575 for raising
and
lowering the operator platform 574 along posts 570a that extend upward from
the
frame 522. As shown in FIG. 18, the platform elevation mechanism 575 may
include
an elevation actuator, such as a hydraulic cylinder 600 located within one of
the
posts 570a. The hydraulic cylinder 600 raises and lowers the operator platform
574
using a system of cables 602 and pulleys 604 located within the posts 570a.
[0161] The platform elevation mechanism 575 may also include a safety
lock
mechanism for securing the operator platform 74 at a specific height. As
shown, the
safety lock mechanism may include an operating valve and a down flow
restrictor
606 on the hydraulic cylinder 600 for preventing sudden movements of the
operator
platform 574. The safety lock mechanism may also include a load chain 608 for
backing up the cable 602 in the event of failure of the cables 602.
[0162] Referring again to FIG. 15, the frame 522 may include a first frame
section
609 for supporting the first and second conveyor sections 525, 526, and a
second
frame section 610 for supporting the third tiltable conveyor section 527.
[0163] The second frame section 610 generally supports the third
tiltable
conveyor section 527 while still allowing the third tiltable conveyor section
527 to
pivot up and down about the second horizontal axis H2. For example, the second
frame section 610 may be pivotally coupled to the first frame section 609 by a
first
link arm 612, and pivotally coupled to the third tiltable conveyor section 527
by a
second link arm 614. The first link arm 612 may be rigidly attached to the
second
frame section 610 and may be pivotally coupled to the frame 522 at a pivot
point P1.
The second link arm 614 may be rigidly attached to the third tiltable conveyor
section
527 and may be pivotally coupled to the second frame section 610 at a pivot
point
P2.
[0164] As shown, the second pivot point P2 may be a rolling-sliding
connection.
For example, the second frame section 610 may have a guide slot 616 that
slidably
and rotatably receives a pin 618 on the second link arm 614. Furthermore, the
guide
slot 616 may be oriented generally perpendicular to the second link arm 614.
This
CA 02854306 2014-06-13
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allows the second frame section 610 to support the third tiltable conveyor
section
527 through the second link arm 614 while still allowing the third tiltable
conveyor
section 527 to pivot up and down about the second horizontal axis H2. This can
be
useful when the extendable conveyor 516 is a powered flex conveyor (as shown
in
FIGS. 14 and 15), which might not be capable of supporting the third tiltable
conveyor section 527 on its own.
[0165] As shown, the second frame section 610 may include one or more wheels
620 for engaging the ground and supporting the second frame section 610. The
first
frame section 609 can also be supported by wheels 672, 673. Furthermore, some
of
the wheels may be motorized wheels for driving the frame 522. For example, the
rear wheels 672 of the first frame section 609 may be motorized, while the
front
wheels 673 may be caster wheels. Accordingly, the conveyor apparatus 520
operates as a rear wheel drive vehicle with skid steering capabilities. For
example,
when turning the conveyor apparatus 520, one motorized wheel 672 rotates
faster
than the other motorized wheel 672, and the caster wheels 673 swivel freely in
response to movement of the conveyor apparatus 520. The motorized wheels 672
may also be rotated in opposite directions to provide a tighter turning
radius.
[0166] In other embodiments, the wheels 672, 673 may have other
configurations
and the conveyor apparatus 520 may be driven in other modes such as front
wheel
drive, four-wheel drive, and the like. The apparatus 520 could also include
other
types of steering mechanisms.
[0167] In some embodiments, the apparatus 520 may include an on-board
battery for powering the motorized wheels 672. This allows the apparatus to be
self-
propelled, which can be particularly beneficial when the extendable conveyor
516 is
a flexible conveyor that is not capable of being extended or retracted on its
own. The
apparatus 520 could also be connected to an external power source (e.g. using
an
electrical cable).
[0168] Referring now to FIG. 19, the apparatus 520 may include one or
more belt
tensioners for maintaining tension along the conveyor belts. For example, as
shown
in FIG. 19, there is a belt tensioner 680 underneath the first conveying
surface 540.
The belt tensioner 680 includes a tension roller 682 for pressing against a
conveyor
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belt 684. An actuator 686 (shown in FIG. 16) is coupled to the tension roller
682 for
moving the tension roller 682 along a path 688 towards or away from the belt
684 or
to increase or decrease pressure applied to the belt 684, and thus, increase
or
decrease tension. The actuator 686 can be controlled by a source of fluid
pressure
such as pneumatic or hydraulic pressure source, or another biasing element
such as
a compression spring. This can help maintain a desired tension on the conveyor
belt
684, which may reduce bearing loading and/or belt stretching.
[0169] Referring again to FIG. 14, the apparatus 520 may include one or
more
sensors 660, 662, 664, 666 for detecting objects along the conveying surfaces
540,
541, 542. The sensors 660, 662, 664, 666 may be optical sensors, proximity
sensors, and the like.
[0170] In some examples, the sensors 660, 662, 664, 666 can be used to
control
speed of the conveying surfaces 540, 541, 542. This may allow objects to be
cued
on the conveying surfaces 540, 541, 542, for example, when loading objects
into a
shipping container.
[0171] For example, the first and second sensors 660, 662 may detect
objects
travelling along the first conveying surface 540. More particularly, the first
sensor
660 may detect objects approaching the free end 532 and may stop the first
conveying surface 540 before the object would otherwise fall off the free end
532.
The second sensor 662 may detect objects approaching the first sensor 660 and
may be configured to slow the first conveying surface 540 prior to reaching
the free
end 532. This may provide the operator with more time to pick up and load the
object into the shipping container.
[0172] The first sensor 660 may also be configured to detect the hands
of an
operator. For example, the sensor 660 may have a line-of-sight 661 directed
slightly
above the first conveying surface 540. If the operator's hands are detected in
the
line-of-sight 661, it may indicate that the operator is ready to load the next
object into
the shipping container, and thus, the first sensor 660 may over-ride the speed
decrease that would otherwise occur due to the second sensor 662. This may
help
increase throughput instead of continuously slowing down the first conveying
surface
540.
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[0173] The third sensor 664 may detect objects travelling along the
second
conveying surface 541. For example, the third sensor 664 may have a line-of-
sight
665 that extends through slots 670 underneath the side guides 590, 592. The
third
sensor 664 may be configured to slow or stop the second conveying surface 541,
for
example, if one or more objects have accumulated on the first conveying
surface
540. This may allow objects to be cued on the second conveying surface 541.
[0174] The fourth sensor 666 may detect objects travelling along the
third
conveying surface 542. For example, the fourth sensor 666 may be located near
the
rear end 533 of the third tiltable conveyor section 527. The fourth sensor 666
may be
configured to slow or stop the third conveying surface 542, for example, if
one or
more objects have been accumulated on the second conveying surface 541. This
may allow objects to be cued on the third conveying surface 542. The fourth
sensor
666 may also be configured to slow or stop the extendable conveyor 516, for
example, if one or more objects have accumulated on the third conveying
surface
542.
[0175] As described above, the conveying surfaces 540, 541, 542 may be
operated in forward or reverse to either load or unload objects from a
shipping
container. For example, with reference to FIG. 14, the conveying surfaces 540,
541,
542 may be configured to load objects into a shipping container by conveying
objects from the extendable conveyor 516 toward the free end 532. In this
case,
each of the conveying surfaces 540, 541, 542 may be powered conveyor belts.
[0176] Alternatively, the conveying surfaces 540, 541, 542 may be
configured to
unload objects from a shipping container by conveying objects from the free
end 532
toward the extendable conveyor 516. This operation may require one or more
modifications to the apparatus 520. For example, with reference to FIG. 20,
the
transition plates 560, 562 may be reversed so that the first transition plate
560 is
located above the second transition plate 562 instead of being underneath the
second transition plate 562. Furthermore, the side guides 590, 592 may be
reconfigured compared to the orientation shown in FIG. 14. These modifications
may
reduce the likelihood of objects becoming jammed when unloading objects from
the
shipping container.
CA 02854306 2014-06-13
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[0177] The apparatus 520 may also be modified to include an additional set
of
side guides 596 along the first conveying surface 540. This may help prevent
objects
from falling off the first conveying surface 540 when being unloaded from a
shipping
container.
[0178] Furthermore, when unloading objects, the conveyor sections 525, 526,
527 may be reconfigured so that the driven roller of each conveyor belt is
located
toward the rear (i.e. closer to the extendable conveyor 516). This may help
maintain
tension along the conveyor belts. In contrast, the driven rollers may be
located near
the front of each conveyor belt when loading the shipping container.
[0179] When unloading objects from a shipping container, the third
conveying
surface 542 may be replaced with a gravity feed conveyor, which may include
rollers
for feeding packages to the extendable conveyor 516 under the force of gravity
instead of using a powered conveyor.
[0180] While the description herein may refer to various directional
qualifiers such
as horizontal, vertical, front, rear, top and bottom and the like, these and
other
directional qualifiers are meant only to aid in describing the embodiments and
should
not be read as limiting.
[0181] What has been described is merely illustrative of the application of
the
principles of the embodiments. Other apparatus, methods and systems can be
implemented by those skilled in the art without departing from the scope of
the
invention, which is defined in the appended claims.
