U.S. patent application number 09/814317 was filed with the patent office on 2002-02-07 for all wheel steer variable load carrying tractor vehicle.
This patent application is currently assigned to Ag-Chem Equipment Company, Inc.. Invention is credited to McQuinn, Alvin E..
Application Number | 20020014188 09/814317 |
Document ID | / |
Family ID | 23172568 |
Filed Date | 2002-02-07 |
United States Patent
Application |
20020014188 |
Kind Code |
A1 |
McQuinn, Alvin E. |
February 7, 2002 |
All wheel steer variable load carrying tractor vehicle
Abstract
An all wheel steer variable load carrying tractor vehicle which
is particularly suited for towing crop input implements, the front
section of which comprises a cab and engine the back section of
which comprises several storage containers for carrying bulk crop
inputs. The storage containers are releasably attached to the
vehicle and can be changed based on the type of crop inputs applied
and any implements towed by the vehicle. The vehicle is equipped
with all wheel steering to increase maneuverability. The vehicle is
also equipped with high flotation tires or tracks to minimize soil
compaction. A delivery system in combination with a control system
coordinates the movement of the crop inputs from the vehicle to
places located off the vehicle.
Inventors: |
McQuinn, Alvin E.; (Bonita
Springs, FL) |
Correspondence
Address: |
KINNEY & LANGE, P.A.
THE KINNEY & LANGE BUILDING
312 SOUTH THIRD STREET
MINNEAPOLIS
MN
55415-1002
US
|
Assignee: |
Ag-Chem Equipment Company,
Inc.
5720 Smetana Drive, Suite 100
Minnetonka
MN
55343
|
Family ID: |
23172568 |
Appl. No.: |
09/814317 |
Filed: |
March 21, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09814317 |
Mar 21, 2001 |
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09303536 |
Apr 30, 1999 |
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6253691 |
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Current U.S.
Class: |
111/200 |
Current CPC
Class: |
A01C 15/006 20130101;
Y10S 111/925 20130101; A01C 23/006 20130101; A01C 7/208 20130101;
Y02P 60/21 20151101; A01C 23/00 20130101 |
Class at
Publication: |
111/200 |
International
Class: |
A01C 003/00; A01C
005/00; A01C 007/18; A01C 001/00 |
Claims
1. A load carrying towing vehicle, the vehicle comprising: a frame
having a front portion carrying an engine and a cab, and a rear
portion which is longer than the front portion and which is sized
to receive crop input storage container means for carrying bulk
crop input, wherein the weight of the container means is greater
than the weight of the frame, such that the weight of the container
means contributes a substantial portion of total vehicle weight to
provide the vehicle with adequate traction for towing a crop input
applicator; a hitch for connecting the crop input applicator to the
vehicle; and steerable front and rear low impact ground engaging
means and a steerable articulated joint supported by the frame.
2. The load carrying towing vehicle of claim 1 wherein the
container means is sized to permit application of crop input to a
field without a need for towing a crop input storage device.
3. The load carrying towing vehicle of claim 1 wherein the capacity
of the crop input storage container means is greater than 50% of
the total amount of crop input carried by the vehicle and the towed
crop input applicator.
4. The load carrying towing vehicle of claim 1 wherein the
container means holds wet bulk crop input.
5. The load carrying towing vehicle of claim 1 wherein the
container means holds dry bulk crop input.
6. The load carrying towing vehicle of claim 1 wherein the front
and rear low impact ground engaging means comprise a plurality of
tracks.
7. The load carrying towing vehicle of claim 1 wherein the front
and rear low impact ground engaging means comprise a plurality of
high flotation tires.
8. The load carrying towing vehicle of claim 1 wherein the front
and rear low impact ground engaging means comprise a combination of
high flotation tires and low impact tracks.
9. The load carrying towing vehicle of claim 1 and furthering
comprising a transfer means for transporting crop input from the
crop input container means to an agricultural field.
10. The load carrying towing vehicle of claim 9 wherein the
transfer means moves crop input from the frame to the towed crop
input applicator for application to a field.
11. The load carrying towing vehicle of claim 9 wherein the
transfer means is waste spreader.
12. A load carrying towing vehicle, the vehicle comprising: a light
weight frame having a front portion carrying an engine and cab, and
having a rear portion which is longer than the front portion; a
plurality of crop input storage containers for carrying bulk crop
inputs removably attached to the rear portion of the frame, wherein
the containers contribute a substantial portion of total vehicle
weight to provide the vehicle with adequate traction for towing a
crop input applicator; and a steerable rear ground engaging means
and steerable front ground engaging means.
13. The load carrying towing vehicle of claim 12 wherein the
capacity of the crop input storage containers is greater than 50%
of the total weight of crop inputs carried by the storage
containers on the vehicle and the towed crop input applicator.
14. The load carrying towing vehicle of claim 12 wherein the light
weight frame is sized to provide space for receiving the plurality
of load carrying crop input storage containers.
15. The load carrying towing vehicle of claim 12 wherein the weight
of the containers is greater than the weight of the frame.
16. The load carrying towing vehicle of claim 12 wherein the crop
input storage containers are sized to permit application of crop
inputs to a field without a need for towing a crop input storage
device.
17. The load carrying towing vehicle of claim 12 and furthering
comprising means for transferring crop inputs from the crop input
storage containers to an agricultural field.
18. The load carrying towing vehicle of claim 17 wherein the means
moves for transferring crop inputs from the crop input storage
containers to the towed crop input applicator.
19. The load carrying towing vehicle of claim 17 wherein the means
for transferring is a waste spreader.
20. The load carrying towing vehicle of claim 12 wherein at least
one of the plurality of containers holds wet bulk crop input.
21. The load carrying towing vehicle of claim 12 wherein at least
one of the plurality of containers holds dry bulk crop input.
22. The load carrying towing vehicle of claim 12 wherein the front
and rear ground engaging means are low impact.
23. The load carrying towing vehicle of claim 22 wherein the front
and rear low impact ground engaging means are a plurality of
tracks.
24. The load carrying towing vehicle of claim 22 wherein the front
and rear low impact ground engaging means are a plurality of high
flotation tires.
25. The load carrying towing vehicle of claim 22 wherein the front
and rear low impact ground engaging means are a combination of high
flotation tires and tracks.
26. The load carrying towing vehicle of claim 12 and further
comprising an articulated joint supported by the frame.
27. The load carrying towing vehicle of claim 12 wherein the crop
input storage containers removably attached to the rear portion of
the frame comprise interchangeable top mounted bins.
28. The load carrying towing vehicle of claim 12 wherein the crop
input storage containers removably attached to the rear portion of
the frame comprise interchangeable top mounted tanks.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] The present application is a divisional of U.S. patent
application entitled All Wheel Steer Variable Load Carrying Tractor
Vehicle, Ser. No. 09/303,536, filed Apr. 30, 1999.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a load carrying tractor type
vehicle to be used in general and site specific farming operations.
It has multiple uses and many different systems can be affixed to
or towed by the vehicle, but it is particularly adaptable for
carrying multiple crop inputs associated with fertilizing and
planting crops. More particularly, this invention relates to a
tractor vehicle with all wheel steering configured to carry a
payload of multiple crop inputs where the crop input storage
containers are replaceable and exchangeable, but may be permanently
affixed in some unique situations to accommodate specific
applications. The all wheel steering facilitates accurate row
tracking, turning maneuverability, and minimizes side slippage of
the vehicle or towed implements on a hill.
[0003] To improve efficiency, farmers are moving to larger
implements in an attempt to combine operations in one pass and thus
decrease the time and expense it takes to make several trips over
the same field. Likewise, more than one implement may be towed so
that still more crop inputs can be applied in one pass through the
field. For example, a tractor vehicle used for planting seeds may
tow a planting implement as well as a holding tank containing the
seeds to be planted. If other crop inputs are applied during
planting, additional storage containers or holding tanks are
required to accommodate transporting those crop inputs, and must
likewise be towed behind the tractor vehicle.
[0004] The increase in the size and number of implements towed
behind tractors, as well as the need to increase the size of
tractors so that they are able to pull the larger implements or
combinations of them, leads to more destruction of the soil and
more compaction. Soil compaction prevents moisture penetration,
reduces fertilizer and chemical utilization, and hinders root
growth. Thus, less soil compaction means higher yields and the
fewer wheels or tracks that follow the tractor the better.
[0005] Another result of the increasing size and number of
implements pulled behind a tractor vehicle is that more room is
required at the end of the row for the vehicle and implements to
turn around. When several crop inputs are applied requiring several
holding tanks to be towed behind the tractor, much more area must
be left at the end of the field for the tractor, implements, and
tanks to turn around. This area used for turning may not be worked,
and often must be covered in another pass around the perimeter of
the field. When the turning radius of the vehicle and implements is
large, it may take more than one perimeter pass to cover the
unworked ground, which takes more time. A further problem with such
a large turn radius is that it makes it more difficult to start the
next row without missing some ground or overlapping ground already
covered.
[0006] Time is also spent filling the crop input containers each
time they are emptied. This may require a farmer to unload seed
bags or otherwise keep a supply of crop inputs nearby for refilling
the holding tanks as they become empty. This becomes even more time
consuming when multiple crop inputs are applied at different rates,
which may cause the farmer to stop and refill different crop inputs
at different times, greatly slowing the application process.
[0007] Historically, farm tractors have been built with enough
weight to allow for adequate traction relative to the farm
implements to be pulled. Not enough weight meant wheel slippage and
poor performance with its many undesirable and unacceptable
negative characteristics. Because the tractors were designed to be
heavy enough to achieve the desired traction, tractors did not have
a load carrying platform for multiple crop inputs and large volumes
of crop inputs. Adding a payload of crop inputs would simply make
the tractors too heavy to be useful.
[0008] To further increase efficiency and compete in the global
market, farmers are increasingly turning to high technology to help
them plant, fertilize, and apply chemicals in a manner that reduces
costs while increasing yields. Precision farming uses a global
positioning system (GPS), site specific maps, and computer systems
on board the tractor vehicle to aid a farmer in applying the
precise amount of crop inputs required by the soil conditions of a
particular point in a field. More sophisticated precision farming
systems can coordinate the application of multiple crop inputs so
that the correct prescriptive mix is applied as required by soil
conditions for a particular point in a field.
[0009] Accordingly, there is a need in the farming industry for a
load carrying tractor vehicle having appropriate weight
distribution and steering capability to prevent row track side
slippage of the tractor vehicle when operating on hillsides.
Likewise, there is a need for a vehicle that can carry a large
payload of multiple crop inputs which will not need to be refilled
often and that can accommodate the application of multiple crop
inputs while reducing soil compaction and turning radius. It is a
significant improvement in the art for such a vehicle to be
equipped with the latest technology for precision farming.
BRIEF SUMMARY OF THE INVENTION
[0010] The present invention answers the need in the agricultural
industry for a tractor vehicle that operates on steep hills or
grades without the rear of the vehicle slipping downhill, even when
towing one or more implements or crop input storage devices or
both. The invention reduces soil compaction and turning radius, and
yet is able to apply multiple crop inputs in one pass. The present
invention is an all wheel steering variable load carrying tractor
vehicle capable of operating with a control system for coordinating
application of multiple crop inputs consistent with site specific
farming goals.
[0011] To make it easier to turn around and keep rows aligned, the
vehicle has all wheel steering. Thus when traveling on hills, the
rear of the vehicle can be steered so that it continues to follow
the front of the vehicle, rather than slipping downhill. The all
wheel steering likewise helps to turn the towing vehicle more
sharply at the end of a row and make it possible to start the next
row with little or no skips or overlaps. To further increase
maneuverability, the vehicle may be articulated, and configured
with articulated steering. It is also possible to have the vehicle
articulated with both articulated steering and rear axle
steering.
[0012] Towing a large load through a field can disrupt the soil,
especially due to slippage on hillsides or in wet areas. This soil
disruption is alleviated by moving the payload from behind to on
the vehicle. The all wheel steering load carrying vehicle is fitted
with multiple containers on the rear section of the vehicle,
allowing the vehicle to carry a payload of multiple crop inputs.
This eliminates much of the need for towing a separate crop input
storage tank behind the vehicle. By eliminating at least one
implement behind the vehicle, less soil compaction occurs with each
pass through a field. To further reduce soil compaction, the towing
vehicle is fitted with either high flotation tires or tracks.
[0013] The all wheel steer variable load carrying tractor vehicle
is designed with less weight. In the past, tractor vehicles were
designed to be heavy enough to achieve the desired traction. Since
the tractor vehicles were already heavy, adding a payload for
storing crop inputs would make the tractor too heavy for most
farming uses. The present invention has smaller castings, a light
weight extended frame, and other components that have been
minimized to eliminate weight. This allows for installation of
various combinations of application tanks and bins, which allow for
the desired combination of crop inputs to fit the required farming
application. This construction also allows the vehicle to transport
a payload of multiple crop inputs onboard with no increase in soil
compaction or soil disruption.
[0014] Since planter loads of seeds, fertilizer, and crop
protection chemicals can be carried on the tractor vehicle, the
quantity of inputs carried on the planter can be reduced or
eliminated. This makes it possible to design and use planters that
are easier to fold for road transportation because storage tanks
may be unnecessary on the planter or drill. The variable load
carrying tractor offers similar benefits when it is used to apply
fertilizer, fertilizer in conjunction with crop protection
chemicals, and any of many other various other crop input
combinations.
[0015] The multiple containers carried on the rear section of the
towing vehicle are removable and changeable. This increases the
flexibility for farmers in that multiple crop inputs can be applied
in one pass without needing to tow other implements. Likewise,
farmers can choose the type of containers that best meet their
needs based on the type of towed implement and the type of crop
inputs to be applied. The containers can carry a combination of wet
or dry or both crop inputs. The term crop inputs means, but is not
limited to, seeds, fertilizers, including micronutrients,
pesticides, including insecticides, herbicides, fungicides, and any
other soil amendment or addition of any kind used to facilitate
crop growth. Also included are specialty products, such as N serve,
which does not directly affect the crop, but preserves nitrogen
applied in anhydrous ammonia. The containers have a large capacity,
which increases efficiency by eliminating the need to stop and
refill implements which have a smaller capacity. Thus, farmers do
not have to struggle with bags of seed or jugs of chemical.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a perspective view of a prior art tractor having
multiple towed crop input storage tanks and a crop input applicator
implement attached to a three-point hitch.
[0017] FIG. 2 is a perspective view of a variable load carrying
towing vehicle with an articulated frame, a variable dry/wet
payload system, and a towed crop input applicator.
[0018] FIG. 3 is a top view of a variable load carrying towing
vehicle with an articulated frame and a bare chassis.
[0019] FIGS. 4A and 4B are top views of a variable load carrying
vehicle with an articulated frame and illustrating articulated
steering.
[0020] FIG. 4C is a top view of a variable load carrying vehicle
with articulated steering and illustrating rear axle steering.
[0021] FIG. 4D is a top view of a variable load carrying vehicle
with articulated steering and illustrating all wheel steering.
[0022] FIG. 5A is a top view of a non-articulated variable load
carrying vehicle with all wheel steering.
[0023] FIG. 5B is a top view of a non-articulated variable load
carrying vehicle with all wheel steering commonly called crab
steering.
[0024] FIG. 6A is a top view of a variable load carrying vehicle
with two front wheels and four rear wheels.
[0025] FIG. 6B is a top view of a variable load carrying vehicle
with eight wheels; dual front and dual rear wheels.
[0026] FIG. 7A is a top view of a variable load carrying vehicle
illustrating a single bin capacity with a side wet tank.
[0027] FIG. 7B is a top view of a variable load carrying vehicle
illustrating a twin bin capacity with dual side wet tanks and rear
tracks.
[0028] FIG. 7C is a top view of a variable payload vehicle
illustrating a three bin capacity with no side wet tanks and front
and rear tracks.
DETAILED DESCRIPTION
[0029] FIG. 1 is a perspective view of a prior art crop input
applicator system 10 including a tractor vehicle 12, a towed
storage bin 14, a seeding implement 16, and a towed spreader 18.
The towed storage bin 14 is attached to the tractor vehicle 12 by a
three point hitch 20 in a manner well known to those skilled in the
art. This system 10 is typical of site specific planting practices,
where it is common to require simultaneous transportation of
several crop inputs (seed, bulbs, fertilizer, herbicide,
insecticides, and fungicides) and applicators (planters, spreaders,
toolbars, and storage tanks) to achieve several operations in one
pass. When on a steep hillside, the spreader 18, implement 16, and
storage bin 14 tend to slip downhill, making the system 10 hard to
control. In addition, the system 10 becomes very long in such a
"mule train" set up, which requires a much larger turning radius.
Likewise, the amount of soil compaction generated by the tractor
12, the storage bin 14, the implement 16, and the spreader 18 can
be significant due to the number of tires that traverse the
soil.
[0030] FIG. 2 shows one embodiment of an all wheel steer variable
load carrying vehicle 40 towing an accompanying crop input
applicator 42. The vehicle 40 has an articulated frame 44 with a
front section 46 and a rear section 48. The front section 46
carries the cab 50 and the engine compartment 52, which encloses
the engine. The rear section 48 is longer than the front section 46
and is configured to selectively and removably carry dry crop input
containers 54, 56, 58, and a wet crop input container 60. Also on
the rear section 48 is a hitch 62. The vehicle 40 is designed to be
lighter weight than conventional tractor vehicles so that when
full, the containers 54-60 do not make the vehicle 40 so heavy as
to be impractical for use. To achieve this, the vehicle 40 has
smaller castings, an extended light weight frame 44, and other
components that have been minimized to eliminate weight.
[0031] The extended light weight frame 44 is sized to allow for
installation of the crop input storage containers 54-60. The weight
of the containers 54-60 is greater than the weight of the frame 44
so that the containers 54-60 contribute the substantial portion of
the total vehicle weight. The weight of the containers 54-60 gives
the vehicle 40 enough traction to tow an accompanying applicator
42, even though the vehicle has a light weight frame 44. In
addition, the containers 54-60 allow the farmer to assemble the
desired combination of crop inputs to fit the required farming
application. Thus, the farmer can determine which crop inputs need
to be applied, select a crop input applicator 42 to be towed behind
the vehicle 40, and configure the storage containers 54-60 on the
vehicle 40 to match both the applicator 42 and type of crop inputs
to be applied.
[0032] This configuration is a significant improvement over current
tractors. Most tractor vehicles are designed to be heavy enough to
achieve the desired traction necessary to tow a large implement
through a field. Since the tractor vehicles are already heavy,
adding a payload for storing crop inputs would make the tractor too
heavy for most farming uses. Thus, the present invention is a
significant improvement in the art.
[0033] Likewise, since planter loads of seeds, fertilizer, and crop
protection chemicals can be carried on the tractor vehicle 40, the
quantity of inputs carried on the planter can be reduced or
eliminated. As a result, planters and drills that are easier to
fold and easier to transportation down roads can be designed
because the storage tanks are unnecessary. The variable load
carrying tractor 40 offers similar benefits when it is used to
apply fertilizer, fertilizer in conjunction with crop protection
chemicals, and any of many other various other crop input
combinations.
[0034] The variable payload towing vehicle 40 is capable of
carrying several crop inputs in the containers 54-60. The dry
containers 54, 56, and 58 are configured to hold dry crop inputs,
such as seed, bulbs, granular fertilizer, and other types of dry
fertilizer, herbicide, or insecticide. In addition to the dry
containers 54, 56, and 58, the towing vehicle 40 is also configured
with a side container 60 capable of holding wet crop inputs. The
wet container 60 can be used for such things as liquid fertilizer,
liquid herbicide, liquid insecticide, liquid fungicide, or other
such liquid crop inputs. One of the major benefits of the variable
payload vehicle 40 is its ability to carry large quantities of
multiple crop inputs and dispense them to a towed crop input
applicator 42. Because of this large capacity, the variable payload
vehicle 40 is a significant improvement in the art in that it does
not require a farmer to stop and struggle with bags of seed or jugs
of chemical to maintain a full supply of multiple crop inputs on
the applicator 42.
[0035] All the containers 54-60 on the rear section 48 are
releasably attached to the frame 44. In this manner, the containers
54-60 are changeable and offer a farmer increased flexibility to
vary containers 54-60 depending on the type of crop input
applicator 42 used and the type of crop inputs being applied.
Access to the dry containers 54, 56 and 58 is through container
covers 64, 66, 68 where the crop inputs can be loaded. It is also
possible to permanently attach the containers 54-60 to the frame
44. Likewise, it is possible to simply add weights to the vehicle
40 so that it can be used as a towing vehicle without filling the
crop input storage containers 54-60. Adding weights will give the
vehicle 40 the desired weight so that it has the needed
traction.
[0036] The vehicle 40 is particularly suited to towing a crop input
applicator 42. The hitch 62 makes it possible for a wide variety of
types of crop input applicators 42 to be attached to the vehicle
40. Though the crop input applicator 42 shown in FIG. 2 is a type
of planter, other types of applicators 42 may be used in connection
with the towing vehicle 40, including other types of planters,
drills, fertilizer applicators, toolbars, or similar implements.
When towing a crop input applicator 42, the crop inputs stored in
the containers 54-60 must be moved from the vehicle 40 to any towed
applicator 42, and therefore, the towing vehicle 40 is equipped
with a delivery system 70.
[0037] The delivery system 70 can be used to move crop inputs from
the towing vehicle 40 to a towed crop input applicator 42, and it
is also possible for the delivery system 70 to be used in the
absence of a towed vehicle to dispense crop inputs directly from
the vehicle 40 to the agricultural field. The delivery system 68
shown in the present embodiment is air assisted, however, other
delivery systems are possible, such as a spreader, spray boom, or a
combination thereof. To assure the vehicle 40 and any towed crop
input applicator 42 are capable of working consistent with
precision farming goals, the vehicle 40 may likewise be equipped
with a control system and a locating system, such as a GPS
receiver.
[0038] The towing vehicle 40 is designed to reduce soil compaction,
and thus is equipped with high floatation tires 72 and 74. Other
configurations assuring low impact on the soil include equipping
the towing vehicle 40 with tracks or a combination of tracks and
high flotation tires. Both high floatation tires and tracks are
well known to those skilled in the art.
[0039] The vehicle 40 shown in FIG. 2 is an articulated vehicle,
having an articulated joint 76 connecting the front section 46 and
the rear section 48. FIG. 3 is a more detailed view of an
articulated variable load carrying tractor. FIG. 3 is a top view of
a variable load carrying vehicle 80 more clearly illustrating how
the front section 82 and rear section 84 are connected by an
articulated joint 86. Cab 88 and engine 90 are illustrated on the
front section 82. The rear section 84 is shown with no containers
attached, but rather as the bare frame 92. The articulated joint 86
used between the front section 82 and rear section 84 is commonly
known to those skill in the art. FIG. 3 illustrates how the
articulated joint 86 acts as the pivot point for the towing vehicle
80.
[0040] As mentioned before, a common problem with large crop input
systems is the difficulty in controlling the system on steep
hillsides. The rear of the tractor vehicle, and the towed implement
or implements, often tend to slip down the hillside, making it
extremely difficult to accurately follow the rows without skips or
overlaps. The present invention greatly alleviates this problem due
to the steering system employed by the vehicle. FIGS. 4A-4D show
top views of the towing vehicle 80 illustrating the vehicle's
steering system.
[0041] FIG. 4A shows an articulated variable payload towing vehicle
80 with articulated joint 86. FIG. 4A illustrates the position of
the front wheels 94 and rear wheels 96 when the vehicle 80 is
traveling in a straight line. As can be seen, the the rear wheels
94 follow directly behind the front wheels 96. FIG. 4B shows how
the variable payload vehicle 80 is steered using articulated
steering at the articulated joint 86. The joint 86 includes of a
pair of actuators that pivot the joint allowing the front section
82 to move relative to the rear section 84. When using articulated
steering as illustrated in FIG. 4B, neither the front wheels 96 nor
the rear wheels 94 of the towing vehicle 80 are turned.
[0042] In contrast, FIG. 4C shows the articulated variable payload
towing vehicle 80 with a rear steering system. As can be seen on
FIG. 4C, the rear wheels 94 are steered as well as steering the
articulated joint 86. The effect of the rear axle steering in FIG.
4C is for the front section 82 to be steered by the articulated
joint 86 followed closely by the rear section 84 due to rear wheel
94 steering. In this manner, the rear section 84 can be controlled
so that it follows the front section 82 more closely. Rear axle
steering also helps to keep the rear section 84 aligned with the
front section 82 on steep hillsides when normally the rear section
84, or any towed implement, slips downhill. Further, the rear wheel
94 steering allows the vehicle 80 to have a much tighter turning
radius.
[0043] FIG. 4D shows yet another embodiment of a variable payload
towing vehicle 80 with an articulated joint 86. In FIG. 4D, it is
apparent that the rear wheels 94 are steerable as well as the front
wheels 96. Having all wheels steerable further reduces the turning
radius of the towing vehicle 80. All wheel steering increases the
maneuverability of the towing vehicle 80 and can be used to offset
any slippage experienced by the towing vehicle 80 or any towed
implements when used on a hillside. As mentioned above, the rear
wheels 94 and the front wheels 96 may be fitted with either high
flotation tires, tracks, or a combination of both.
[0044] Though the embodiments shown in FIGS. 2, 3, and 4A-4D all
show the variable load carrying vehicle with an articulated frame,
the present invention is not so limited. FIGS. 5A and 5B illustrate
the present invention with a non-articulated frame configured with
rear axle steering and all wheel steering (front and rear axle
steering). FIG. 5A is a top view of a load carrying vehicle 100.
The front wheels 102 and rear wheels 104 are both steerable
allowing the vehicle 100 to make a tight turn. As the front wheels
102 turn the vehicle 100, the rear wheels 104 closely follow the
path of the front wheels 102, moving the vehicle 100 in a circular
path. The result of the configuration of the front 102 and rear 104
wheels is a direction of travel indicated by arrow 16.
[0045] FIG. 5B illustrates a variable load carrying vehicle 100
with all wheel steering. The vehicle 100 of FIG. 5B has front
wheels 102 and rear wheels 104 both steered in the same direction.
When so steered, the vehicle 100 moves in the direction of travel
indicated by arrow 108. In such an instance, the rear wheels 104 do
not follow in the same path as the front wheels 102. This steering
configuration is sometimes referred to as crab steering. Crab
steering as illustrated in FIG. 5B is particularly useful in a load
carrying vehicle 100 because when towing implements on steep
hillsides, the rear of the vehicle 100, as well as any towed
implements, begins to slip downhill, in the direction indicated by
arrow 110.
[0046] By steering the rear wheels 104, it is possible to react to
this downhill slippage and keep the vehicle 100 aligned with the
previous row. Without all wheel steering, the operator of a vehicle
100 towing an implement must continuously steer to compensate for
the slippage of the vehicle 100 and implement downhill. First, the
vehicle 100 must be turned uphill to compensate for the slippage.
The resulting path of the vehicle 100 is a wavy path, since once
the slippage has been compensated for, the vehicle 100 is often
overlapping the previous row, and must be turned back downhill to
align itself. Thus, the flexibility allowed from all wheel steering
makes the vehicle 100 much more maneuverable on steep
hillsides.
[0047] As illustrated in FIGS. 5A and 5B, the variable load
carrying vehicle 100 is capable of more than one steering mode.
Namely, the vehicle 100 can utilize the all wheel steering for
turning, as shown in FIG. 5A, or for crab-like movement, as shown
in FIG. 5B. Likewise, when the vehicle has an articulated joint, as
shown in FIGS. 4A-4D, the vehicle has several steering modes. When
articulated, the vehicle may have articulated steering only,
articulated steering with front wheel steering, articulated
steering with rear wheel steering, or articulated steering with all
wheel steering. These very different steering modes are operator
selectable from the cab of the vehicle. By making it possible for
the operator of the vehicle to choose the appropriate steering mode
based on current conditions, the operator has increased flexibility
and maneuverability.
[0048] Though the embodiments shown in FIGS. 2-5B all have four
wheels, the variable load carrying vehicle may have a variety of
wheel configurations; the vehicle may be four wheeled, six wheeled,
or even eight wheeled. FIG. 6A shows a top view of a variable load
carrying vehicle 110 with six wheels. The vehicle 110 has two front
wheels 112, and four wheels 114, 116 on the rear of the vehicle.
FIG. 6B shows a variable load carrying vehicle 120 equipped with
eight wheels. The vehicle 120 has front dual wheels 122 and rear
dual wheels 124. Other combinations of wheel configurations are
also possible.
[0049] Though the embodiment shown in FIG. 2 illustrates three dry
containers 48-52, and one wet container 56, it is possible for the
vehicle to be configured with a different set of containers. For
instance, FIG. 7A is a top view of a variable payload vehicle 130
showing that instead of containing three separate dry containers,
the variable payload towing vehicle 130 is configured with one
large container 132, and still carries one side tank 134 for wet
crop inputs. In addition, as depicted in FIG. 7B, it is possible to
operate the towing vehicle 130 with two wet tanks 136 and 138 and a
twin bin 140 with a first compartment 142 and a second compartment
144 for dry crop inputs. Unlike the storage containers shown in
FIGS. 2, the twin bin shown in FIG. 7B is not enclosed, allowing
easy access from any point above the bins and eliminating a need
for access covers. In still another configuration, FIG. 7C
indicates a vehicle 130 without any wet tanks, but with three bins
136, 138, and 140 for dry crop inputs. It is also possible to mount
an anhydrous ammonia tank on the frame.
[0050] Also visible in FIGS. 7A-7C are different configurations of
low impact ground engaging means comprising the front wheels 152
and the rear wheels 154. FIG. 7A shows a variable payload vehicle
130 with high flotation tires 156 on both the front wheels 152 and
rear wheels 154. FIG. 7B shows a variable payload vehicle 130 with
both tires 156 and tracks 158. In FIG. 7B, the vehicle 130 is
equipped with high flotation tires 156 on the front wheels 152 and
tracks 158 on the rear wheels 154. Another configuration is shown
in FIG. 7C, where the vehicle 130 is equipped with tracks 158 on
both the front wheels 152 and rear wheels 154. Other combinations
of tires and tracks are also possible. For instance, when both
tires 156 and tracks 158 are used on a vehicle it is most preferred
to have tracks 158 on the rear wheels 154. It is also possible to
have a combination of tires 156 and tracks 158 wherein the tracks
158 are placed on the front wheels 152 and the tires 156 are placed
on the rear wheels 154.
[0051] Although the present invention has been described with
reference to preferred embodiments, workers skilled in the art will
recognize that changes may be made in form and detail without
departing from the spirit and scope of the invention.
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