Note: Descriptions are shown in the official language in which they were submitted.
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CARGO_CONVEY_R SYSTEM
TECHN I CAL FI ELD
The present invention relates generally to conveyor
systems. More particularly, the present invention relates
to a conveyor system ~or handling cargo in warehouses and
the like. Specifically, the present invention relates to a
roving conveyor system to interface with other fixed conveyor
systems of a warehouse to facilitate transportation of cargo
between a cargo storage area and the other conveyor systems.
Furthermore, the present invention relates to a cargo
handling conveyor system wherein the overall structure is
movable relative to a cargo storage area thereby providing
easy access to a greater amount of the storage area.
~CKGRoUND ART
Cargo handling systems employing conveyors are
~uite common in storage warehouses and the like. Such
systems generally employ a continuously moving conveyor belt
on which travels the material being handled, which material
may be in the form of individual articles or boxes, bags or
similar bundles. In more elaborate systems, a plurality of
conveyor belts, travelin~ in different directions, are
employed, such that material can be transported simultane-
ously to various locations about the warehouse.
However, where such multi-directional conveyor
systems are desired and employed, they are usually not fully
reversible resultin~ in limited usability of the system.
Because the change in dlrection is most often accomplished
by merely permitting the cargo to drop from a conveyor
traveling in one direction to a second conveyor traveling in
an angular directiont the possibility of reversin~ the
travel of the system, as is often desired, does not exist.
Furthermore, in warehouses having most types of
known conveyor systems, workers are re~uired to add and
remove material from the continuously moving conveyor belt
at the appropriate locations. The workers also must
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transport the material b~tween the conveyor belt and the
physical location where the material is stored.
~ hen the material is quite ~ea~y and/or when the
distance between the conveyor and the physical storage
location is great, the workers are strained to keep the
material handling rate as high as possible. As a result,
more workers or additional equipment, such as fork-lift
trucks, are required to keep up with the flow of material on
the continuously moving conveyor. Alternatively, additional
conveyor systems can be installed thereby minimizing the
distances from the various physical storage areas. However,
such additional co~veyor sys~ems are costly, require addi-
tional floor space otherwise available for storage, and do
not resolve the problems the worker faces when handling
heavy material.
Despite the many warehouse facilities in existence,
and the continuing need to handle material efficiently~ with
minimal man-power, no known material handling system is
available to efficiently transport material between a continu-
ally moving conveyor and a storage area or cargo carrier,
particularly if the material is heavy and/or the distance
from the conveyor is ~reat.
DISCLOSURE OF THE INVENTION
It is, therefore, a primary object of the present
invention to provide a conveyor system for handling cargo or
similar materials.
It is further object of the present invention to
provide a conveyor system, as above, which is usable with
existing conveyor systems in warehouses and the like.
It is another object of the present invention toprovide a conveyor system, as above, which is ~ully revers-
ible to facilitate transporting cargo or similar materials
between the existing conveyor systems and a storage area or
cargo carrier.
It is yet a further ob~ect of the present inv0ntion
to provide a conveyor system, as above, which is mobile
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throughout a warehouse.
It is still another object of the present invention
to provide a conveyor system, as above, having position-
able conveyors to provide access to storage areas, and the
like, remote from an existing conveyor system.
These and other objects of the invention, as well
as the advan~ages thereof over existing and prior art forms,
which will be apparent in view of the following specifi-
cation, are accomplished by means hereinafter described and
claimed.
In general, a system for conveying cargo or the
like, according to the concept of the present invention,
includes a movable gantry and a first conveyor boom carried
by the gantry. Similarly, a second conveyor boom is carried
by the gantry for rotation relative to the gantry and the
first conveyor boom. A first turntable is interposed between
the first conveyor boom and the second conveyor boom, and is
rotatably positionable relative thereto.
A method for handling cargo on a conveyor system,
according to the concept of the present invention, and
having a first conveyor, a second conveyor and a turntable
conveyor interposed therebetween includes the step of posi-
tioning the second conveyor relative to the first conveyor.
The orientation of the first conveyor relative to the second
conveyor is determined and the turntable conveyor is thereby
oriented relative to the first and second conveyors.
An exemplary, preferred embodiment of a conveyor
system, incorporating the concept of the present invention,
is shown by way of example in the accompanying drawings
without attempting to show all the various forms and modifi-
cations in which the invention mi~ht be embodied, the
invention being meas~lred by the appended claims and not by
the details of the specification.
35~RIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic elevational view of a cargo
conveyor system embodying the concept of the present inven-
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tion;
Fig. 2 is a schematic top plan view of the cargo
conveyor system of Fig. l;
Fig~ 3 is an enlarged fragmentary elevational view
o~ the gantry turntable of the cargo conveyor system of Fig.
l; and,
Fig. 4 is an enlarged fragmentary elevational view
of the boom platform of the cargo conveyor system of Fiq~ 1.
EXEMPLARY EMB~DIMENT FOR CARRYING OUT_THE INVENTION
A conveyor system according to the concept of the
present invention, and suitable for handling car~o and the
like, is indicated generally by the numeral 10 in Fig. 1 of
the accompanying drawings. The cargo conveyor system 10 is
depicted in a warehouse environment, interfacing with a pair
of conveyors 11 and 12 moving in opposite directions, as
depicted in Fig. 2. Generally, such conveyors 11 and 12
travel throughout the warehouse, or interface with a con-
veyor network, to move cargo or similar material between the
various areas of the warehouse and cargo carriers.
The cargo conveyor system 10 includes a mobile
gantry 13 which can travel throughout the warehouse. Prefer-
ably, gantry 13 straddles conveyors 11, 12 and is guided by
rails 14 on which drive wheels lS ride. In this manner, the
cargo conveyor system 10 can travel throughout the regions
of the warehouse accessed by conveyors 11, 12.
Gantry 13 may be positioned adjacent conveyors 11,
12 or distant there~rom, as opposed to straddling the same.
~ikewise, gantry 13 may be guided other than by rails 14, or
it may be freely controlled and steered by an operator. The
advantages of the embodiment disclosed in the drawings are
that the cargo carrier system 10 remains at all times func-
tionally positioned relative to conveyors 11, 12. Further-
more, by straddling conveyors 11, 12, minimal additional
floor space is required for the car~o conveyor system 10.
Rails 14 also may be used to carry suitable conductors to
provide power to the cargo carrier system 10 and to interface
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electrically the cargo carrier system 10 with a central
controller, if desired, as would be known in the art.
Preferably, drive wheels 15 are driven by a suit-
able prime mover, for example electric motors, to translate
the cargo conveyor system 10 along rails 14, as depicted in
Fig. 1. Such motors may be powered internally, as by on-
board batteries, or they may be powered from an external
source as discussed hereinabove.
A base 20 is rotatably carried on gantry 13, for
rotation about a vertical axis C, as shown in Fig. 2, using
a suitable bearing structure 21. Such bearing structure 21
would be well known to one skilled in the art such that a
detailed discussion need not be presented herein. It is
expected, of course, that bearing structure 21 be suffi-
ciently sized to handle the thrust and radial loads trans-
mitted by base 20. Bearing structure 21 preferably also
includes suitable actuacing means to facilitate rotation of
base 20 relative to gantry 13. Such actuating means would
be well known to the skilled artisan and may include a ring
and pinion gear assembly with a suitable prime mover. Of
course, it may be desirable not to have an actuating means
and, instead, to allow the operator to move and position
base 20 by hand. In any event, it is preferred that base 20
can rotate at least approximately 330 about vertical axis
C, approximately 165 to either side of the longitudinal
axis of gantry 13. The actual limits of rotation will
depend on the requirements of the installation.
A boom 22 is rotatably mounted on gantry 13 to
rotate coaxially relative to base 20. A suitable bearing
structure 23 provides for such rotation and may be identical
to bearing structure 21 discussed hereinabove. While boom
22 rotates coaxially relative to base 20, it is preferred
tha~ the two rotate independently of each other. According-
ly, it is preferred that bearing structure 23 and any corres-
ponding actuatinq means, if so desired, be mounted on thesuperstructure of gantry 13~ It, likewise, is preferred
that boom 22 be capable of rotating at least approximately
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240 about vertical axis C, approximately 120 to either
side of the longitudinal axis of gantry 13, and generall~
diametrically opposite the rotation of base 20. ~s with
base 20, the limits of rotation will depend on the require~
ments oE the installation.
Boom 22 includes a downwardly inclined leg 24
forming a cantilever frame structure for a conveyor belt
assembly 25. Such a conveyor belt assembly 25 is well known
in the material handling industry and need not be described
in detail herain. It is preferred that conveyor belt
assembly 25 be capable of reversible direction of travel, as
will be appreciated hereinbelow. It also is preferred that
conveyor belt assembly 25 extend along the full length of
boom 22 and that the lowermost end 26 of boom 22 be suitably
positionable above warehouse conveyors 11, 12 to in~erface
therewith for handling of cargo, as would be appreciated by
one skilled in the art.
The uppermost end 30 of boom 22 presents a substan-
tially planar region on which conveyor belt assembly 25 also
~0 is carried. Upper end 30 aligns elevationally with a similar
upper surface 31 of base 20. A conveyor belt assembly 32 is
incorporated onto upper surface 31. Again, conveyor bel~
assembly 32 is a typical conveyor capable of reversible
direction of travel.
Interposed between base 20 and boom 22, and aligned
elevationally with upper end 30 of boom 22 and upper surface
31 of base 20, is a ~antry turntable assembly 33. The
construction of turntable 33 may be more fully considered
and described with reference to Fig. 3.
Specifically, turntable 33 includes a suitable
framework 34 supporting a platen 35. Turntable 33 is carried
by gantry 13 to be coaxially rotatable relative to base 20
and boom 22 using a suitable bearing structure 36 similar
to bearin0 structures 21 and 23 as heretofore described. As
depicted in Fig. 3, an exemplary bearing structure 36 may
have the outer race 37 thereof secured to the bottom of
framework 34 and an inner race 38 secured to gantry 13.
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Inner race 38 also may define an internal ring gear 40
about the inner periphery thereo~. Ring gear 40 may inter-
face with a suitable pinion gear 41 coupled to an electric
gearmotor 42 carried by framework 34. Such an arrangement
provides a suitable actuator to control the rotational
movement of turntable 33, as would be appreciated by one
skilled in the art. A conventional angular position encoder
43 is operatively interconnected with the output shaft of
gearmotor 42 as by mating ~ears 44 and 45. In this manner,
the angular position of turntable 33 relative to gantry 13
can accurately be determined, as would be appreciated by the
skilled artisan in the field. It should be appreciated that
the fore~oing assembly presents an effective actuator to
control the rotational movement of turntable 33. In like
fashion, similar asse~blies may be employed as the respec-
tive actuators for base 20 and boom 22, heretofore discussed.
Such actuators may not only control the movement o~ the base
20 and boom 22, but also will determine the respective
angular positions thereof for purposes which will be appre-
ciated hereinbelow.
Turntable 33 includes a suitable conveyor beltassembly 46. As depicted in Fig. 3, conveyor belt assembly
46 may be a typical conveyor system including a continuous
conveyor belt 50 operatively interconnected to a suitable
motor 51 as by drive belt 52. A typical slack adjuster 49
is provided to maintain the appropriate tension in conveyor
belt 50. Conveyor belt assembly 46 preferably is capable of
reversible direction of travel as will be appreciated herein-
below. The specific structure and components of conveyor
belt assembly 46, including the controllers thereEore, are
all well known to those skilled in the art of cGnVeyOrS and
need not be embellished upon herein. The concept of the
present invention is attainable using a wide variety of
conveyor assemblies and should not be limited to any one
conveyor assembly disclosed herein.
Referring again to Fig. 1, an extendable conveyor
53 is pivotally connected to the radially distal end of
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upper surface 31 of ~ase 20 as by hinge 54 so as to be
selectively movable to a variety of discharge levels as
shown in Fig. lo Extendable conveyor 53 is rotated about
hinge 54 by one or more suitably sized boom actuators 55,
interposed between base 20 and extendable conveyor 53. Boom
actuators 55 may be hydraulic cylinders or, more preferably,
electromechanical cylinders capable of pivotin~ extendable
conveyor 53 through an arc of approximately 40, although
this may vary according to the needs of the user.
Extendable conveyor 53 includes a fixed boom 56
and a retractable boom 57 telescoped to fixed boom 56. A
suitable, reversible conveyor belt assembly 60, similar to
those heretofore discussed, extends along substantially the
full length of extendable conveyor 53 with suitable slack
adjustment to permit the conveyor belt assembly 60 to
remain operational through the range of extension of extend-
able conveyor 53, which may be approximately 13 eet (3.9m).
While different extendable conveyors 53 may be employed to
meet the needs of the user, for purposes of this disclosure,
one suitable type of conveyor has been found to be the
~AnJusTovEyoR extendable conveyor, manufactured by Stewart-
Glapat Corp. of Zanesville, Ohio.
The outermost end of extendable conveyor 53 carries
a boom platform 61. As depicted in Fig. 1, boom platform 61
is pivotably mounted to the distal end of retractable boom
57 by hinge pin 62. A suitable actuator 63, preferably
hydraulic or electromechanical, is suitably connected between
a clevis 64 on retractable boom 57 and a clevis 65 on the
support frame 66 of boom platform 61, as depicted in Fig. 4,
to regulate the orientation of boom platform 61 relative to
extendable conveyor 53. As would be appreciated by one
skilled in the art, actuator 63 may be.controlled by a
suitable tilt sensor affixed to boom platform 61 such that
actuator 63 is appropriately energized to maintain boom
platform 61 substantially level at all positions of extend-
able conveyor 53. Of course, suitable manual control of
actuator 63 may be provided to enahle boom plat~orm 61 to be
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positioned in other than a horizontal position to meet the
needs of the user.
A conveyor belt assembly 70 may be provided on
support frame 66 to interface with conveyor belt assembly 60
of extendable conveyor ~3. Conveyor belt assembly 70 may be
identical in structure and operation as conveyor belt
assembly 32 of base 20.
Similarly, a platform turntable 71, which can be
identical to qantry turntable 33, includes a similar conveyor
belt assembly 72 which can be suitabl~ mounted on support
frame 66 with a bearing structure 73 which may be identical
to bearing structure 36. As such, the specific structure of
platform turntable 71, conveyor belt assembly 72, or bearing
structure 73 need not be described in detail herein with the
understandin~ that such are identical to gantry turntable
33, conveyor belt assembly 46 and bearing structure 36,
respectively, unless otherwise indicated.
Support frame 66 also carries a swing frame 74
underhung there~rom. A suitable bearing structure 75 permits
swing frame 74 to rotate relative to support frame 66 along
an axis common with platform turntable 71. Bearing structure
75 may be identical to any of the bearing structures hereto-
fore disclosed and descrihed. As depicted in Fig. 4, bearing
structure 75 may include an inner race 80 secured to the
bottom of support frame 66. An outer race 81 is secured to
the horizontal leg 82 of swing frame 74. The outer periphery
of outer race 81 also may define an external ring gear 83
which mates with a suitable pinion gear 84, coupled to an
electric gearmotor 85 mounted on support frame 66.
A conventional angular position encoder 86 is
operatively interconnected with external ring gear 83 by
gear 87. Accordingly, the angular position of swing frame
74 relative to support frame 66 can be determined, and, in
conjunction with gearmotor 85, can be controlled. Of course,
the foregoing describes an effective embodiment enabling and
controlling the rotational movement of swing frame 7~, but
it is not the exclusive embodiment. Indeed, the structures
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which permit rotation of turntables 33 and 71, or those o-E
base 20 and boom 22 may all be similar in configuration and
operation, as would be appreciated by one skilled in the
art.
Swing frame 74 carries a conveyor belt assembly 90
similar to conveyor belt assembly 70, to in-terface with
conveyor belt assembly 72 of platform turntable 71. A
pivotal deck 91 is affixed to the distal end of swing frame
74 by a suitable hinge 92. An actuator 93, again preferably
hydraulic or electromechanical, is operatively interconnected
between deck 91 and swing frame 74 to pivot deck 91 about
hinge 92 as may be desired by the user. It should be appre-
ciated that deck 91 provides a final adjustable platform
which may he positioned suitably to facilitate handling of
cargo by the worker, as will be discussed hereinbelow.
While the range through which deck 91 may be positioned will
vary depending upon the needs of the user, it has been found
to be desirable for dack 91 to pivot from approximately 10
above a horizontal plane to approximately 20 therebelow.
~eck 91 also may include a conveyor belt assembly 94 similar
to conveyor belt assembly 90 and capable of interfacing
therewith.
The ~oregoing provides a general description of
the overall structure of a cargo conveyor system 10 embody-
ing the concept of the present invention. ~owever, to morefully understand and appreciate the present invention, it is
desirable to consider the operation of the same in conjunc~
tion with the handling of cargo. Discussion will be directed
to a cargo conveyor system 10 installed in a warehouse
having warehouse conveyors 11 and 12 traveling in opposite
directions. As previously discussed herein, rails 14 are
provided on either side o~ warehouse conveyors 11 and 12 and
gantry 13 of the carqo conveyor system 10 is suitably
positioned to travel therealong.
The cargo conveyor system 10 is first positioned
along rails 14 to be in the general vicinity of the warehouse
where cargo will be handled. Boom 22 is then positioned
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such that lower end 26 o~ leg 24 is positioned to interface
with the appropriate warehouse conveyor, for example the
outbound conveyor 11. ~oom platform 61 is positioned adja-
cent to the cargo in the warehouse that will be unloaded.
Positioning of boom platform 61 is accomplished by rotation
of base 20; raising or lowering, and extending or retracting
retractable boom 57; pivoting of swing frame 74; and raising
or lowering of deck ~1. As discussed hereinabove, such
positioning of the components of the cargo conveyor system
10 can be accomplished manually or through use of suitable
controls mounted on ~antry 13 or elsewhere, as would be
appreciated by the skilled artisan. The purpose of the
positioning is to achieve the minimal distance possible
between the end of deck 91 and the area where the cargo is
stored in the warehouse or the cargo area of a carrier, such
as a railcar or a truck trailer, for example.
Orientation of gantry turntable 33 and platfor~
turntable 71 is effected automatically and simultaneously
with the positioning of base 20 and boom 22, for gantry
turntable 33, and swing frame 74, for platform turntable 71.
Specifically, with reference to Fig. 2 and gantry turntable
33, the interior angle defined by the position of base 20
and boom 22 is determined by the respective angular posi~ion
encoders as heretofore discussed. The signals from these
encoders may be fed into a suitable logic controller, of a
type well known in the art, which then controls the position-
ing of gantry turntable 33 such that the line of travel of
conveyor belt assembly 46 preferably is oriented at an angle
which is a percentage of the supplement oE the angle defined
by the orientation of boom 22 relative to base 20. Such
percentage is predetermined by the operator and is usually
dictated by the type of cargo being conveyed.
In similar fashion, as hereinabove discussed, a
suitable anqular position encoder determines the position of
swing frame 74 relative to support frame 66. The signal,
likewise, is fed to the logic controller which in turn
positions platform turntable 71 such that the line of travel
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of conveyor belt assembly 72 preferably is oriented at an
angle which is a percentage of the supplement of the angle
defined by the orientation of swing frame 74 relative to
sup~or~ frame 66. A~ain, such percentage is determined by
the operator and is usually dictated by the type of cargo
being conveyed.
When the car~o conveyor system 10 has been
positioned properly, it is energized to run in the proper
mode -- for example a discharge mode. All the conveyor
assemblies heretofore discussed will travel in the same
general direction at approximately the same speed, as would
be appreciated by one skilled in the art~
With the cargo conveyor system 10 operating in
this fashion, car~o can be removed from the storage area of
the warehouse. Specifically, the warehouse worker places
the cargo, in the form of bundles or boxes or the like, onto
conveyor belt assembly 94 of deck 91. From there the cargo
travels onto conveyor belt assembly 90 to conveyor belt
assembly 72 of platfor~ turntable 71; and then onto conveyor
belt 70 to retractable boom 57. Conveyor belt assembly 60
moves the cargo along to conveyor belt assembly 32 on base
20 which in turn transfers the cargo to conveyor belt
assembly 46 of gantry turntable 33. The cargo is then
routed to conveyor belt assembly 25 of boom 22 which
deposits it onto outboard conveyor 11 of the warehouse
conveyor network for ro~lting to another area of the ware-
house.
It should be appreciated that, to receive inbound
cargo for storage in the warehouse, the foregoing operation
is simply reversed -- with all the conveyor assemblies
traveling in the reversed, inbound direction. ~oom 22 is
positioned such that lower end 26 aligns with inbound ware-
house conveyor 12 to receive cargo therefrom. Thereafter,
the warehouse worker removes the cargo from conveyor belt
assembly 90 of deck 91 and places it as desired for storage
or subsequent handling.
The foregoinq provides one exemplary embodiment of
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a conveyor system incorporating the concept of the present
invention. It should be evident that alterations and modi-
fications, which are obvious to one skilled in the art, can
be made to the foregoing disclosed embodiment without
departing from the concept of the invention. Indeed, it may
be desirable to have more or less turntables, retractable
booms, conveyors or articulated members than those disclosed
herein, to meet the reguirements of a specific user. Like-
wise, the manner in which the ~antry travels, or the cargo
conveyor system is powered or controlled, can be modified to
meet the specific needs of the user.
Therefore, it should be appreciated that a
conveyor system embodying the concept of the present
invention disclosed herein provides an efficient and
flexible manner for handling and transporting any materials
such as cargo, including bags, bundles, boxes and the like
in a warehouse environment. Accordingly, it should be
evident that a cargo conveyor system as disclosed herein
carries out the various objects of the invention and other-
wise constitutes an advantageous contribution to the art.
