Note: Descriptions are shown in the official language in which they were submitted.
TANDEM STEERING FOR A GRAIN CART
The present invention relates to a grain cart and more particularly to a wheel
assembly for
the grain cart to allow a set of tandem wheels on the grain cart to pivot
together in
combination.
BACKGROUND
Grain carts are typically used to transfer grain or other crop material from a
combine
harvester to a grain truck or bin. The grain cart typically comprises a
storage hopper for
crop material, an auger assembly for emptying crop material from the storage
hopper and
a set of ground wheels so that the grain cart can be towed. While smaller
grain carts
may have a single pair of wheels, larger grain carts now commonly have a
tandem set of
wheels (two wheels on each side of the grain cart). A tractor is commonly used
to tow
the grain cart with the auger assembly of the grain cart being driven off of
the power
take off (PTO) of the tractor (although hydraulics, etc. could also be used to
power
the auger assembly).
In use, the gain cart is towed by the tractor to a combine harvester where the
crop
material is unloaded from the combine harvester into the grain cart. With the
crop
material loaded into the storage hopper of the grain cart, the tractor can tow
the grain cart
to a truck, trailer, storage bin, etc. and use the auger system to unload the
crop material
from the grain cart.
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Grain carts are getting larger and larger and some are now quite large. The
larger grain
carts now use tandem wheels on each side of these grain carts so that these
larger grain
carts are supported by four wheels in total. However, these tandem wheels can
make it
hard to turn the grain cart if the wheels are fixed in position. Instead, it
is desirable to
.. have a wheel assembly that allows the wheels to pivot when the grain cart
is turned in
order to allow the wheels of the grain cart to follow a curved path while the
components
used in the wheel assembly are relatively simply and still allow the wheels to
be fixed in
place to make it easier or even possible to reverse the grain cart.
SUMMARY OF THE INVENTION
.. In a first aspect, a grain cart is providing having a frame, a hitch
assembly attached to a
front end of the frame, a storage hopper provided on the frame, an auger
assembly
operatively connected to the storage hopper to discharge particulate material
from the
storage hopper out of the grain cart and a wheel assembly attached to the
frame. The
wheel assembly can include a first side suspension member, a second side
suspension
.. member, a first side front wheel rotatively and pivotally connected to a
front end of the
first side suspension member, a first side rear wheel rotatively and pivotally
connected to
a rear end of the first side suspension member, a second side front wheel
rotatively and
pivotally connected to a front end of a second side suspension member, a
second side rear
wheel rotatively and pivotally connected to a rear end of the second side
suspension
member, a first side steering link assembly operatively coupling the pivoting
of the first
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side front wheel and the first side rear wheel so that the first side front
wheel and the
second side rear wheel pivot in opposite directions, a second side steering
link assembly
operatively coupling the pivoting of the second side front wheel and the
second side rear
wheel so that the second side front wheel and the second side rear wheel pivot
in opposite
directions and a unison linkage assembly operatively coupling the pivoting of
the first
side rear wheel and first side front wheel with the pivoting of the second
side rear wheel
and the second side front wheel.
In a further aspect, a grain cart can be provided wherein the first side
steering link
assembly includes a first side rear suspension link connected to a first
steering arm of the
first side rear wheel, a first side bell crank having a first side and a
second side, the first
side of the first side bell crank connected to the first side rear suspension
link and a first
side front suspension link connected to a steering arm of the first side front
wheel and the
second side of the first side bell crank.
In a further aspect, a grain cart can be provided wherein the first side
steering link
assembly includes a first side rear suspension link connected to a first
steering arm of the
first side rear wheel, a first side bell crank having a first side and a
second side, the first
side of the first side bell crank connected to the first side rear suspension
link, and a first
side front suspension link connected to a steering arm of the first side front
wheel and the
second side of the first side bell crank.
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In a further aspect, a grain cart is provided wherein the unison linkage
includes a first
side cross linkage connected to a lower steering ann of the first side rear
tire, a first cross
bell crank having a first side and a second side, the first side connected to
the first side
cross linkage, a second cross bell crank having a first side and a second
side, a second
side cross linkage connected to a lower steering arm of the second side rear
tire and the
first side of the second cross bell crank and a rod member connected between
the second
side of the first cross bell crank and a second side of the second cross bell
crank.
DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention is described below with
reference to the
accompanying drawings, in which:
FIG. 1 is a perspective view of a grain cart;
FIG. 2 is a side view of the grain cart of FIG. 1;
FIG. 3 is a top view of the grain cart of FIG. 1;
FIG. 4 is a front view of the grain cart of FIG. 1 with the auger assembly in
an
operating position;
FIG. 5 is a front view of the grain cart of FIG. 1 with the auger assembly in
a
transport position;
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FIG. 6 is a partial view of the bottom of a storage hopper of a grain cart
with
openings to a transport assembly;
FIG. 7 is a partial view of the bottom of the storage hopper of FIG. 6 with
the
openings closed by gates; and
FIG. 8 is a perspective view of a wheel assembly of the grain cart of FIG. 1;
FIG. 9 is a top view of the wheel assembly of FIG. 8; and
FIG. 10 is a bottom view of the wheel assembly of FIG. 8.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
FIGS. 1-5 illustrates a grain cart 10. The grain cart 10 can have a frame 20,
ground
wheels 210, 220, 260 and 270, a hitch assembly 40, a storage hopper 60 for
storing crop
material and an auger assembly 80. Crop material can be loaded into the
storage hopper
60 of the grain cart 10 for transport to another location. When the grain cart
10 has been
towed by a tow vehicle to another location, the auger assembly 80 can be used
to unload
the crop material from the storage hopper 60 out of the gain cart 10.
.. The frame 20 can support the storage hopper 60 and the wheels 210, 220, 260
and 270
can be operatively attached to the frame 20. The hitch assembly 40 can be
connected to
the front of the frame 20 and the hitch assembly 40 can then be hitched to a
tow vehicle,
such as a tractor (not shown), to tow the grain cart 10.
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The storage hopper 60 has an interior portion for storing crop material. The
upper side
walls 62 of the storage hopper 60 can be relatively vertical while the lower
walls 64 can
be angled inwards to direct crop material into a center portion 66 at the
bottom of the
hopper 60. Crop material loaded into the storage hopper 60 will be directed by
gravity
towards the center portion 66 in the bottom of the storage hopper 60.
FIGS. 6 and 7 shows the center portion 66 in the bottom of the storage hopper
60.
Typically, a screen can be provided over the center portion 66, but it is not
shown in
these figures to better illustrate the components in the center portion 66.
The center
portion 66 of the storage hopper 60 can have a series of selectively openable
gates 72 and
corresponding openings 74 beneath the gates 72. Beneath these openings 74 a
transport
assembly 70 for moving crop material that has fallen through the openings 74
and into
the transport assembly 70 can be provided. The transport assembly 70 can move
crop
material that has fallen through the openings 64 towards the front of the
grain cart 10 and
into the auger assembly 80. In the auger assembly 80, the crop material can be
moved up
the auger assembly 80 to be discharged out of the grain cart 10. The transport
assembly
70 is typically a pair of augers and corresponding auger housings, but it can
also be a
conveyor belt, etc. However, in some grain cart 10, such as corner-auger
designs, the
intake of the auger assembly 80 can be provided beneath the openings 74 and
the
transport assembly 70 can be a hopper, passage, etc. that directs crop
material into the
intake of the auger assembly 80.
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FIG. 4 illustrates a front view of the grain cart 10 where the auger assembly
80 is in an
operating position ready to discharge crop material out of the grain cart 10
and into an
adjacent truck, trailer, storage bin, etc. and FIG. 5 shows the auger assembly
80 folded up
into a transport position. The auger assembly 80 can have a lower auger
section 110 and
an upper auger section 120. When the auger assembly 80 is in the operating
position, the
upper auger section 120 and the lower auger section 110 can be positioned
coaxial to one
another.
The lower auger section 110 and the upper auger section 120 can each have a
driveshaft
and auger flighting within. The auger fighting in the lower auger section 110
will
convey crop material up the lower auger section 110 and the auger fighting in
the upper
auger section 120. The lower auger section 110 can have an intake end 112 that
is joined
with the outlet of the transport assembly 70 so that crop material that has
reached the end
of the transport assembly 70 is conveyed into the intake end 112 of the lower
auger
section 110. This crop material will then be conveyed up the lower auger
section 110 by
the fighting in the lower auger section 110 until it reaches a top end 114 of
the lower
auger section 110. From the top end 114 of the lower auger section 110, the
crop
material can be transferred to the bottom end 122 of the upper auger section
120 and the
fighting in the upper auger section 120 can convey the crop material up the
upper auger
section 120 to a discharge end 124 of the upper auger section 120.
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The discharge end 124 of the upper auger section 120 can be pivotally
connected to a
discharge assembly 140. A spout 150 can be provided on the discharge assembly
140 to
direct the flow of crop material exiting from the discharge end 140 of the
upper auger
section 120.
When the grain cart 10 is to be transported, especially over relatively long
distances, the
upper auger section 120 can be pivoted around a pivot hinge 130 so that the
upper auger
section 120 is no longer coaxial with the lower auger section 110, but rather,
rotated
around the hinge 130 to be placed closer to parallel with the lower auger
section 110 so
that the upper auger section 120 does not extend significantly beyond the side
of the
storage hopper 60 when the grain cart 10 is in the transport position.
FIG. 8 illustrates a perspective view of the wheel assembly 200 connected to
the frame 20
and used to support the frame 20, the storage hopper 60 and the auger assembly
80. The
wheel assembly 200 has a first side front wheel 210 and a first side rear
wheel 220, both
of which are positioned on a first side of the wheel assembly 200. There is
also a second
side front wheel 260 and a second side rear wheel 270, both of which are
positioned on a
second side of the wheel assembly 200. The wheel assembly 200 allows the
wheels 210,
220, 260, 270, to freely turn when the grain cart 10 is being pulled through a
field and
being turned by the tow vehicle, the wheels 210, 220, 260, 270 are all
operatively
connected to cause the wheels 210, 220, 260, 270 to turn in unison so that the
both the
wheels 210 and 220 on the first side of the wheel assembly 200 and wheels 260
and 270
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on the second side of the wheel assembly 200 pivot and follow a curved path to
allow the
grain cart 10 to be turned easier.
A center section 202 of the wheel assembly 200 can be provided that is
attached to the
frame 20 so that the center section 202 remains fixed relative to the frame
20. The first
side front wheel 210 and the first side rear wheel 220 are operatively
connected to a front
end 212 and a rear end 222 of a first side suspension member 214,
respectively. The
second side front wheel 260 and the second side rear wheel 270 are rotatively
connected
to a front end 262 and a rear end 272 of a second side suspension member 264,
respectively.
The first side front wheel 210 and the first side rear wheel 220 are
rotatively and pivotally
connected to the front end 212 and the rear end 222 of the first side
suspension member
214, respectively. The wheels 210, 220 are rotatively connected such that the
wheels
210, 220 can rotate around the center of the wheel 210, 220 allowing the grain
cart 10 to
move forwards and backwards. The wheels 210, 220 are pivotally connected to
the first
side suspension member 214 such that wheels 210, 220 can pivot around a
vertical axis
and turn in relation to the grain cart 10 and more particularly relative to
the first side
suspension member 214 and the frame 20 of the grain cart 10. Similarly, the
second side
front wheel 260 and the second side rear wheel 270 are rotatively and
pivotally connected
to the front end 262 and the rear end 272 of the second side suspension member
264,
respectively.
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The first side suspension member 214 and the second side suspension member 264
can be
pivotally attached to the center section 202 so that the first side suspension
member 214
and the second side suspension member 264 can pivot around a pivot axis AN
passing
horizontally through the center section 202 and perpendicular to a direction
of travel of
the grain cart 10. In this manner, the first side suspension member 214 can
pivot around
this pivot axis AA', causing the first side front wheel 210 and the first side
rear wheel 220
to be able to angle upwards and downwards relative to the frame 20 of the
grain cart 10
and the second side suspension member 264 can pivot around the pivot axis AA',
causing
the second side front wheel 260 and the second side rear wheel 270 can to be
able to be
angled upwards and downwards relative to the frame 20 of the grain cart 10 to
compensate for changes in the terrain the grain cart 10 is being pulled over.
The pivoting
of the first side suspension member 214 and therefore the angling of the first
side front
wheel 210 and the first side rear wheel 220 can be independent from the
pivoting of the
second side suspension member 264 and therefore the angling of the second side
front
wheel 260 and the second side rear wheel 270.
FIG. 9 illustrates a top view of the wheel assembly 200 showing a first side
steering link
assembly 280 and a second side steering link assembly 290. The first side
steering link
assembly 280 and the second side steering link assembly 290 can be positioned
above the
first side suspension member 214 and the second side suspension member 264,
respectively. The first side steering link assembly 280 can be used to
coordinate the
pivoting of the first side front wheel 210 and the first side rear wheel 220
in tandem and
CA 2959260 2017-02-28
the second side steering link assembly 290 can be used to coordinate the
pivoting of the
second side front wheel 260 and the second side rear wheel 270 in tandem.
The first side steering link assembly 280 can include a first side rear
suspension link 282,
a first side bell crank 285, and a first side front suspension link 288. The
first side rear
suspension link 282 can be connected between a rear steering arm 226 of the
first side
rear wheel 220 to pivot the first side rear wheel 220 relative to the first
side suspension
member 214 and a first side 284 of the first side bell crank 285. The first
side rear
suspension link 282 can be an adjustable tie rod. A first side front
suspension link 288
can be connected between a front steering arm 216 of the first side front
wheel 210 to
pivot the first side front wheel 210 relative to the first side suspension
member 214 and a
second side 286 of the first side bell crank 285. The first side 284 and the
second side
286 of the first side bell crank 285 can be positioned approximately 180 from
each
other. The first side front suspension link 288 can be an adjustable tie rod.
In this manner, when the first side rear wheel 210 pivots, such as when the
grain cart 10
is being towed through a curving path (i.e. turn), the pivoting of the first
side rear wheel
220 will move the rear steering arm 226, which in turn will move the first
side rear
suspension link 282 connected to the first side 284 of the first side bell
crank 285 and
thereby rotate the first side bell crank 285. The rotation of the first side
bell crank 285
will move the first side front suspension link 288 connected to the second
side 286 of the
bell crank 285, which in turn will move the front steering arm 216 and pivot
the first side
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front wheel 210. Because of the configuration of the first side front
suspension link 288,
the first side bell crank 285 and the first side rear suspension link 282, the
first side bell
crank 285 will reverse the direction of motion from the first side rear
suspension link 282
and the first side front suspension link 288 and therefore the first side
front wheel 210
and the first side rear wheel 220 will be pivoted in opposite directions. For
example,
when the first side rear wheel 220 pivots out from a centerline of the grain
cart 10, the
first side front wheel 210 is pivoted in towards the centerline of the grain
cart 10 by the
first side steering link assembly 280 and vice versa.
Similarly, the second side steering link assembly 290 can have a second side
rear
suspension link 292, a second side bell crank 295 and a second side front
suspension link
298. The second side rear suspension link 292 can be connected between a rear
steering
arm 276 of the second side rear wheel 270 to pivot the second side rear wheel
270
relative to the second side suspension member 264 and a first side 274 of the
bell crank
265. The second side rear suspension link 292 can be an adjustable tie rod. A
second
side front suspension link 292 can be connected between a front steering arm
266 of the
second side front wheel 260 to pivot the second side front wheel 260 relative
to the
second side suspension member 264 and a second side 296 of the second side
bell crank
295. The first side 294 and the second side 296 of the second side bell crank
295 can be
positioned approximately 180 from one another. The second side front
suspension link
292 can be an adjustable tie rod.
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In this manner, when the second side rear wheel 270 pivots, such as when the
grain cart
is being towed through a turn, the pivoting of the second side rear wheel 270
will
move the rear steering arm 276, which in turn will move the second side rear
suspension
link 292 connected to the first side 294 of the second side bell crank 295 and
thereby
5 rotate the second side bell crank 295. The rotation of the second bell
crank 295 will
move the second side front suspension link 298 connected to the second side
296 of the
second side bell crank 295. The moving second side front suspension link 298
will in
turn move the front steering arm 266 and pivot the second side front wheel
260. Because
of the configuration of the second side front suspension link 298, the bell
crank 295 and
10 .. the second side rear suspension link 292, the second side bell crank 295
will reverse the
direction of motion from the second side rear suspension link 292 and the
second side
front suspension link 298 and therefore the second side front wheel 260 and
the second
side rear wheel 270 will pivot in opposite directions. For example, when the
second side
rear wheel 270 pivots out from a centerline of the grain cart 10, the second
first side front
wheel 260 is pivoted in towards the centerline of the grain cart 10 and vice
versa.
In addition to the wheels 210, 220, 260 and 270 on each side of the wheel
assembly 200
being operatively coupled together so that the wheels 210, 220, 260 and 270 on
each side
of the wheel assembly 200 pivot in conjunction, the steering components on the
first side
of the wheel assembly 200 and the steering components on the second side of
the wheel
assembly 200 can be operatively connected so that pivoting of the first side
front wheel
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210 and the first side rear wheel 220 will cause the second side front wheel
260 and the
second side rear wheel 270 to pivot as well and vice versa.
The pivoting of the first side suspension member 214 relative to the center
section 202
will not affect the operation of the first side steering link assembly 280
because the first
side rear suspension link 282, the first side bell crank 285 and the first
side front
suspension link 288 will remain fixed in position relative to the first side
suspension
member 214 as the first side suspension member 214 pivots relative to the
center section
202. Similarly, the pivoting of the second side suspension member 264 relative
to the
center section 202 will not affect the operation of the second side steering
link assembly
.. 290 because the second side rear suspension link 292, the second side bell
crank 295 and
the second side front suspension link 298 will remain fixed in position
relative to the
second side suspension member 264 as the second side suspension member 264
pivots
relative to the center section 202.
FIG. 10 is a bottom view of the wheel assembly 200 and a unison linkage
assembly 300
operatively coupling the pivoting of the wheels 210, 220 on the first side of
the wheel
assembly 200 with the pivoting of the wheels 260, 270 on the second side of
the wheel
assembly 200. The unison linkage assembly 300 can connect the first side rear
wheel 220
and the second side rear wheel 270 so that the pivoting of one of these two
wheels 220,
270 causes the other wheel 270, 220 to pivot as well. A first side cross
linkage 310 can
be connected between a lower steering arm 302 of the first side rear wheel 220
and able
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to pivot the first side rear wheel 220 relative to the first side suspension
member 214 and
a first side 314 of a first cross bell crank 315. Similarly, a second side
cross linkage 320
can be connected between a lower steering arm 304 of the second side rear
wheel 270 and
able to pivot the second side rear wheel 270 relative to the second side
suspension
member 264 and a first side 324 of a second cross bell crank 325. A rod member
330 can
be connected between the a second side 316 of the first cross bell crank 315
and a second
side 326 of the second cross bell crank 325.
The rod member 330 can pass through a double rod end hydraulic cylinder 335 so
that the
double rod end cylinder 335 can move the rod member 330 in either direction,
lock the
rod member 330 in place or allow the rod member 330 to "float" or move freely
back and
forth in the double rod end cylinder 335. The double rod end hydraulic
cylinder 335 can
be provided in the center section 202 of the wheel assembly 200.
The rod member 330 can be aligned with the pivot axis AA' so that the rod
member 330
is at the center of the pivot point between the first side suspension member
214 and the
center section 202 and at the center of the pivot point between the second
side suspension
member 264 and the center section 202 so that the first side suspension member
214 and
the second side suspension member 264 pivot around the rod member 330.
The first side 314 and the second side 316 of the first cross bell crank 315
can be
provided at an angle other than 180 so that the first cross bell crank 315
can alter the
direction of motion from the first side cross linkage 310 and the rod member
330. The
CA 2959260 2017-02-28
first side 324 and the second side 236 of the second cross bell crank 325 can
also be
provided at an angle other than 180 so that the second cross bell crank 325
can alter the
direction of motion from the second side cross linkage 320 and the rod member
330.
When the double rod end hydraulic cylinder 335 is placed in the "float" mode,
the rod
member 330 can move freely through the double rod end hydraulic cylinder 335.
The rod
member 330 will mechanically couple the first cross bell crank 315 and the
second cross
bell crank 325, but the rod member 330 will be able to move freely. When the
first side
rear wheel 220 pivots out from the centerline of the grain cart 10, the lower
steering arm
302 connected to first side rear wheel 220 will move the first side cross
linkage 310
which will in turn rotate the first cross bell crank 315. As the first cross
bell crank 315
rotates, the first cross bell crank 315 will pull the rod member 330 and the
rod member
will in turn rotate the second cross bell crank 325. As the second cross bell
crank 325
rotates, the second cross bell crank 325 will push the second side cross
linkage 320 which
will in turn push on the steering arm 304 of the second side rear wheel 270
which will
pivot the second side rear wheel 270 in the same direction as the first side
rear wheel 220
is pivoting, causing the second side rear wheel 270 to pivot in towards the
centerline of
the gain cart 10.
The effect of the pivoting of the first side suspension member 214 and the
second side
suspension member 264 relative to the center section 202 can be reduced by the
placement of the rod member 330 along the pivot axis AN. Unlike the first side
steering
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link assembly 280 and the second side steering link assembly 290 that can move
entirely
with the first side suspension member 214 and the second side suspension
member 264,
respectively, the unison linkage assembly 300 has to connect from the first
side
suspension member 214 across the center section 202 and to the second side
suspension
member 264. Both the first side suspension member 214 and the second side
suspension
member 264 can pivot relative to the center section 202 and independently of
each other.
By having the rod member 330 extend along the pivot axis AN and ends of the
rod
member 330 extend out of the center section 202, the first cross bell crank
315 can
remain fixed in position relative to the first side suspension member 214 and
the second
cross bell crank 325 can remain fixed in position relative to the second side
suspension
member 264. This will allow the first cross bell crank 315, the first side
cross linkage
310 and the steering arm 302 of the first side rear wheel 220 to remain fixed
in position
relative to the first side suspension member 214 as the first side suspension
member 264
pivots relative to the center section 202 and the second cross bell crank 325,
the second
.. side cross linkage 320 and the lower steering arm 304 of the second side
rear wheel 270
to remain fixed in position relative to the second side suspension member 264
as the
second side suspension member 264 pivots relative to the center section 202.
The rod member 330 will stay in position along the pivot axis AA' and the
where the rod
member 330 connects to the second side 316 of the first cross bell crank 315
the end of
the rod member 330 can be pivotally connected so that the end of the rod
member 330
can rotate relative to the second side 316 of the first cross bell crank 315
allowing the
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first cross bell crank 315 to be fixed in positon relative to the first side
suspension
member 214 and move with the pivoting of the first side suspension member 214.
The
connection between the end of the rod member 330 and the second side 316 of
the first
cross bell crank 315 could be a spherical bearing so that the rod member 330
and the
second side 316 allow more relative motion than just rotational motion. In a
similar
manner, where the rod member 330 connects to the second side 326 of the second
cross
bell crank 325 the end of the rod member 330 can be pivotally connected so
that the end
of the rod member 330 can rotate relative to the second side 326 of the second
cross bell
crank 325 allowing the second cross bell crank 325 to be fixed in positon
relative to the
second side suspension member 264 and move with the pivoting of the second
side
suspension member 264. The connection between the end of the rod member 330
and the
second side 326 of the second cross bell crank 325 could be a spherical
bearing so that
the rod member 330 and the second side 326 allow more relative motion than
just
rotational motion.
The unison linkage assembly 300 will cause both the first side rear wheel 220
and the
second side rear wheel 270 to pivot in the same direction. When one of the
first side rear
wheel 220 and the second side rear wheel 270 is pivoted, such as when the tow
vehicle
turns the grain cart 10, and the double end hydraulic cylinder 335 is in
"float" mode, the
other of the second side rear wheel 270 and the first side rear wheel 220 will
be pivoted
in the same direction.
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Referring again to FIG. 9, when the unison linkage assembly 300 causes the
first side rear
wheel 220 and the second side rear wheel 270 to pivot in unison, the first
side steering
link assembly 280 will cause the first side front wheel 210 to pivot in an
opposite
direction to the first side rear wheel 220 and the second side steering link
assembly 290
will cause the second side front wheel 260 to pivot in an opposite direction
to the second
side rear wheel 270.
To back up the grain cart 10 with the tow vehicle, the rod member 330 can be
locked in
place by the double end hydraulic cylinder 335, preventing the first side rear
wheel 220
and the second side rear wheel 270 from pivoting. Because the first side rear
wheel 220
is being held in place by the unison linkage assembly 300, the first side
steering link
assembly 280 will also prevent the first side front wheel 210 from pivoting
and the
second side steering link assembly 290 will prevent the second side front
wheel 260 from
pivoting.
The double end hydraulic cylinder 335 can also be used to pivot the wheels
210, 220,
260, 270 as desired. By routing the hydraulic fluid to the double end
hydraulic cylinder
335 hydraulic fluid, the double end hydraulic cylinder 335 can be used to
force the rod
member 330 to one side or the other, thereby pivoting all of the wheels 210,
220, 260,
270. This can be useful in packing up the grain cart 10 when it has to be
backed into a
specific position instead of straight back or maneuvering the grain cart 10 in
a relatively
tight space.
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The linkages can be adjustable in length so that the amount the first side
front wheel 210
pivots relative to the first side rear wheel 220 and the amount the second
side front wheel
260 pivots relative to the second side rear wheel 270 can be adjusted and set
to a desired
amount The first side rear suspension link 282 and/or the first side front
suspension link
288 can be an adjustable links where the length of the first side rear
suspension link 282
and/or the first side front suspension link 288 can be increased or decreased.
This allows
a person to adjust or "tune" the positioning of the first side front wheel 210
relative to the
first side rear wheel 220 to align the first side front wheel 210 and the
first side rear
wheel 220 to both be pointed straight ahead when the grain cart 10 is being
pulled
forward. Similarly, the second side rear suspension link 292 and/or the second
side front
suspension link 298 can be an adjustable links where the length of the second
side rear
suspension link 292 and/or the second side front suspension link 298 can be
increased or
decreased. This allows a person to adjust or "tune" the positioning of the
second side
front wheel 260 relative to the second side rear wheel 270 to align the second
side front
wheel 260 and the second side rear wheel 270 to both be pointed straight ahead
when the
grain cart 10 is being pulled forward. This can also be used to ensure the
wheels 210,
220 on the first side of the grain cart 10 are parallel with the wheels 260,
270 on the
second side of the grain cart when the grain cart 10 is being pulled straight
ahead. This
can ensure the tires are running true and pointed straight ahead when the
grain cart 10 is
being pulled directly ahead. This can reduce or eliminate any side loading on
the tires,
reduce tire wear and improve the performance of the gain cart 10.
CA 2959260 2017-02-28
The unison link assembly 300 can also be configured so that the amount the
first side rear
wheel 220 pivots relative to the second side rear wheel 270 can be set and
vice versa.
The first side cross linkage 310 and the second side cross linkage 320 can be
adjustable in
length so that the first side rear wheel 220 pivots relative to the second
side rear wheel
270 can be positioned parallel to one another when the grain cart 10 is moving
directly
forward. The configuration of the first side cross linkage 310 and the second
cross bell
crank 325 can be chosen so that the wheels on the outside of a turn to pivot
less than the
wheels on the inside of the grain cart 10 to pivot when the grain cart 10 is
turning with
the wheels on the outside of the turn turning less than the wheels on the
inside of the turn.
This can be accomplished by choosing the size of the first cross bell crank
315 and the
second cross bell crank 325. By choosing a first cross bell crank 315 with a
distance
between the pivot point of the first cross bell crank 315 and the first side
314 of the first
cross bell crank 315 that is greater than the distance between the pivot point
of the first
cross bell crank 315 and the second side 316 of the first cross bell crank 315
and a second
cross bell crank 325 with a distance between the pivot point of the second
cross bell
crank 325 and the first side 324 of the second cross bell crank 325 that is
greater than the
distance between the pivot point of the second cross bell crank 325 and the
second side
326 of the second cross bell crank 325 this can be achieved. Having the amount
the
different wheels pivot curing a turn can reduce the amount of tire scrub on
the ground and
reduce the towing force needed to tow the grain cart 10.
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CA 2959260 2017-02-28
The foregoing is considered as illustrative only of the principles of the
invention.
Further, since numerous changes and modifications will readily occur to those
skilled in
the art, it is not desired to limit the invention to the exact construction
and operation
shown and described, and accordingly, all such suitable changes or
modifications in
structure or operation which may be resorted to are intended to fall within
the scope of
the claimed invention.
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