Note: Descriptions are shown in the official language in which they were submitted.
1
CROP HEADER WITH WING BALANCE CALIBRATION
This invention relates to header of a crop cutting apparatus such as a
swather or a combine harvester which includes multiple sections defining a
center
section and two wing sections where the sections are balanced to maintain a
constant ground force across the width as the total ground force changes and
particularly to a calibration system for the wing balance.
In US Patent 7,918,076 (Talbot) by the present applicants issued April
6th 2011 is disclosed a flex draper header which includes a center section and
two
wing sections that are hinged together. The three header sections are
interconnected with a balance linkage that uses the weight of the header to
keep the
wings in balance and maintain consistent cutterbar pressure across the width
of the
header.
To maintain a balanced ground force distribution across the width of
the header, the interconnecting linkage which attaches the wing frame to the
center
frame requires periodic adjustment.
That is, if the adjustment of the balance system to the wings is set
accurately the wings follow the ground with even ground pressure across the
width
of the header. However if the wings are set with too light a down pressure,
that is the
lift force is too great, the wings will have a tendency to rise and if the
lift force is too
low the wings will have a tendency to fall.
The current adjustment method for adjusting the wing balance requires
the operator to manually measure the force required to move the wing up/down
and
Date Recue/Date Received 2023-08-22
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make an adjustment to the linkage by turning a draw bolt. With this current
adjustment method, proper adjustment of the header is reliant on having the
operator correctly perform these adjustments. Furthermore, it is often not
obvious to
an operator from observation of the operation of the header during harvesting
that
an adjustment is required.
SUMMARY OF THE INVENTION
It is one object of the present invention to provide a calibration system
for the wing balance on a flex header of the above general type which
optimizes the
wing balance settings without the need for the operator to provide input.
According to the invention there is provided a crop harvesting header
for use in a harvesting operation comprising:
a main frame structure extending across a width of the header for
movement in a forward direction generally at right angles to the width across
ground
including a crop to be harvested;
a mounting assembly for carrying the main frame structure on a
propulsion vehicle;
a cutter bar across a front of the main frame structure arranged to
move over the ground in a cutting action;
the main frame structure including a center frame portion, a first wing
frame portion and a second wing frame portion;
each of the wing frame portions being connected to the center frame
portion by a pivot coupling arranged for pivotal movement relative to the
center
Date Recue/Date Received 2023-08-22
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frame portion about a pivot axis extending in a generally forward direction to
positions of the wing frame portion which are in line with, raised above and
lowered
below the center frame portion;
a balance system for applying a lifting force to the center frame portion
and a balanced wing lifting force to each of the wing frame portions to
support the
wing frame portions to provide a balanced ground force distribution across the
width
of the header including the center frame portion and the wing frame portions,
wherein the balance system comprises:
a balance beam having a forward end and a rear end, wherein the
forward end of the balance beam is pivotally connected to the center frame
portion;
a tension link having a first end and a second end, wherein the first
end of the tension link is connected to one of the wing frame portions;
a bell crank having a first arm and a second arm extending from a pivot
point, wherein the first arm of the bell crank includes a slot, the pivot
point of the bell
crank is pivotably connected to the second end of the tension link, and the
second
arm of the bell crank is pivotably connected to the center frame portion; and
a compression link having a first end pivotably connected to the slot in
the bell crank and a second end pivotably connected to the rear end of the
balance
beam; and
an adjustment system arranged to provide adjustment of the balance
system to maintain said balanced ground force distribution, the adjustment
system
comprising:
Date Recue/Date Received 2023-08-22
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at least one sensor repeatedly, over a time period during which
the header is operating in said harvesting operation, detecting data relating
to a
condition of the balance system;
a processor arranged in response to said data sensed by said at
least one sensor to calculate a value representative of said data of the wing
frame
portions over the time period;
the adjustment system effecting an adjustment of the balance
system in response to said value.
The term "balance" as used herein does not require an actual balance
beam to which forces are applied as out in the above patent to Talbot but
other
systems to balance the lifting forces applied to the center section and to the
wing
sections can be provided including arrangements using adjustable springs or
adjustable lift cylinders. For example in US Patent 9968033 (Dunn) issued May
15
2018 and in further published US applications 2018-0153010 and 2018-0153102
the
disclosures of which may be referenced for more information is disclosed a
processor controlled hydraulic cylinder system which provides a lifting force
to a
header. The processor is controlled to adjust the pressure in the cylinders to
provide
a required lift force which can be varied rapidly in response to movement of
the
header. The cylinders can be used on a wing type header to support a center
section relative to the support vehicle and the wings of the header relative
to the
center section. in this arrangement the processor controls the pressure in the
cylinders to provide a controlled lifting force to the sections of the header
with the
Date Recue/Date Received 2023-08-22
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intention of controlling their movement and of maintaining a required ground
force
from the sections to the ground and balancing that ground force between the
sections. Thus the balance system in this embodiment is part of the
programming of
the processor with the programing also providing other responses of the
sections of
the header as set out the above documents. In this arrangement therefore the
adjustment system is a part of the program of the processor so that the
analysis of
the sensor data to calculate a value representative of said data of the wing
frame
portions over the time period is used as an input into the processor to manage
the lift
forces generated so that the ground force is maintained over time balanced
across
the three sections.
There are a number of different ways for the sensor or sensors to
detect the relevant data on the balance system.
In one preferred arrangement the sensor is arranged to detect
positions of each wing frame portion relative to the center frame portion.
This can
be done by directly detecting the relative positions or by detecting the
positions of
each relative to the ground.
In another arrangement, a plurality of sensors operate, for detecting
data relating to a condition of the balance system, by detecting a force
applied by
each of the wing frame portions and the center frame portion to the ground.
That is for example there is provided a plurality of separate ground
engaging elements at spaced positions along the main frame structure for
supporting the cutter bar from the ground and the plurality of separate
sensors are
Date Recue/Date Received 2023-08-22
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each arranged at a respective one of the ground engaging elements for
providing an
output related to a force applied by the header through the respective ground
engaging elements to the ground. These changing forces can be detected and
averaged over time to analyze the amount of time where one sensor is more
loaded
relative to another which is indicative of the relative positions of the wing
frame
portions and the center.
In one preferred example, the sensor operates by detecting movement
of a component of the wing frame portion relative to a component of the center
frame portion. This can be done by detecting a distance between the components
as the pivotal movement of the wing occurs or can be done by detecting the
angle of
the position of the wing at the pivot using a conventional angle detecting
sensor and
providing signals indicative of the changes in the angle as the wing moves up
and
down relative to the center portion.
In another arrangement the sensing system includes a series of
sensors on the center portion and the wing portions and operates by detecting
a
height of each of the wing frame portions and the center frame portion from
the
ground. Even though the ground is changing in height, the measurement over
time
of the height of each portion should provide an average height which is the
same at
each sensor if the balance system is adjusted correctly. If one or both wing
portions
show a difference in height from the ground over the time period, this
provides over
the time period a value which is related to the positions of each wing frame
portion
relative to the center frame portion. This system thus uses the ground as a
Date Recue/Date Received 2023-08-22
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reference location and detects the positions of the center and wing portions
relative
to this reference.
Preferably the system includes at least one sensor for detecting
whether the header is operating in said harvesting operation so that periods
when
the harvester is not operating are discounted from the calculation.
The sensor for detecting whether the header is operating can include a
knife speed sensor but other additional or alternative sensors can be used.
Preferably the processor calculates as said value an indication as to
whether the wing frame portions are predominantly raised or predominantly
lowered
during the time period. This can be done by many different calculations. For
example the system can use an average value of the position over a set time
period.
Alternatively the system can use a summation of values of time during which
the
wings are raised relative to being lowered. The system can use a set time
period
which is then repeated. However calculations can be made which enable the
system to act more quickly than the set time period if significant divergence
from the
average is determined.
Preferably the processor receives and uses in calculation independent
sensor data relating to the independent positions of the wing frame portions
and the
processor determines independent adjustment values for the separate wing frame
portions from the independent sensor data. However the balance system can in
some cases be applied to both wings so that no independent data is required.
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In one example, the processor includes a look up table for determining
an amount of adjustment in relation to the calculated value. That is the
amount of
divergence of the average value calculated from zero can be indicative of a
severe
out of balance situation with the look-up-table providing different values for
adjustment accordingly.
Preferably the processor is arranged such that when the value is within
a predetermined range of acceptability, no adjustment is made. In this way the
system is maintained at a general balance situation unless an out of balance
is
determined beyond the acceptable range.
In order to maintain a track of the adjustments required, the processor
preferably records the new adjustment positon after an adjustment is effected.
Thus, if the wings are set perfectly they will follow the ground with even
ground pressure across the width of the header. However if they are too light,
they
will nominally float up and if they are too heavy they will nominally float
down. It is
assumed for the calculation that the profile of the terrain across the width
of the
header will vary but that when averaged out over a set distance as determined
by
the set period of time of harvesting, the average ground profile across the
width of
the header would be level. Thus the average value of the positions should be
zero.
The system records the wing position while harvesting over a set
period of time. The system uses various sensors to determine if the header is
harvesting. For example, the system acts to record wing position once every
second
over a 15 minute harvesting period and calculate an average wing position over
that
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15 minute period. At the end of the wing position data collection time
interval, an
actuator adjusts the wing balance based on the average wing position value
that
was calculated. If the average wing position is above the in-line position,
the
actuator automatically adjusts the wing balance a set amount, depending on the
calculated average value. This can be a fixed amount but more preferably is
determined from the look-up-table depending on the value of the difference in
average. Once the system has completed the adjustment, it resumes wing
position
data collection and repeats the process which results in continuous
calibration of the
system. When the calculated average position is within a predetermined range
of
acceptability, no adjustment is made.
Thus the system herein uses an actuator to adjust the balance linkage
using an actuator. It will be appreciated that the actual mechanism of the
actuator,
such as a screw or linear actuator can be selected depending on the design of
the
balance system. Thus the system herein provides a method of adjustment using
the
concept that perfectly balanced wings will have the average wing position as
zero or
level at the in-line position after cutting for a set period of time.
In many cases, as defined hereinafter there is provided a central
section mounted on the vehicle and two wing sections, which is in most cases
the
most practical arrangement providing sufficient flexibility without excessive
complication and expense. However the principles of this invention can be
applied to
alternative constructions which allow a plurality of sections to be carried on
a
Date Recue/Date Received 2023-08-22
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propulsion vehicle and for the weight per unit length of each as applied to
the ground
to vary as the total weight is varied.
Thus in one example there may also be two additional outer wing
portions each pivotally mounted to an outer end of the inner wing potion and
each
having a respective pivot coupling and linkage which controls the position of
the
cutter bar as defined herein.
The term "spring" as used in this document is not intended to be limited
to a particularly type of element which provides a spring or biasing force but
merely
defies any element which will allow resilient movement of one component
relative to
another. This can be provided by a mechanical flexing link such as a coil or
tension
spring or can be provided by fluid such as air or hydraulic cylinders and the
term is
also intended to include the suitable mechanical couplings of those links to
the
required elements. Hydraulic cylinders with suitable accumulators for taking
up and
releasing fluid to the cylinders are effective in this regard.
This specification refers to "bending" of the cutter bar. This bending
movement can be obtained by providing a specific hinge between two parts of
the
bar or by providing a cutter bar which can flex sufficiently to accommodate
the
required bending without the necessity for an actual hinge defining a specific
pivot
axis.
The term "skid element" used in the above definition is not intended to
be limited to a particular component of the header and may be provided by any
element which physically engages the ground as the cutter bar and knife
elements
Date Recue/Date Received 2023-08-22
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carried thereby proceed across the ground. Thus the skid element may be
provided
by the cutter bar itself or by an additional component behind the cutter bar.
In
addition, closely spaced rollers or other elements which roll over the ground
and
thus reduce friction may be used provided that the lifting force is spread
evenly
across the cutter bar to provide the floating action to which this invention
is directed,
although this is not generally necessary and not conventionally used.
The mounting assembly may be an adapter frame arranged for
connection of the header to an existing feeder house of a combine harvester.
However such an adapter is not essential and the mounting assembly may be
constituted by simply connecting elements which directly couple the header to
the
combine harvester.
In most cases the header is unsupported by ground wheels such that
all lifting forces from the ground are communicated through an elongate skid
element. However this system can be used where other ground engaging elements
are provided
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described in conjunction with
the accompanying drawings in which:
Figure 1 is taken from US Patent 6,675,568 and shows a schematic
.. rear elevational view of header of the general type with which the present
invention
is concerned with the combine harvester which acts as a propulsion vehicle and
the
associated adapter being omitted for convenience of illustration. A sensor
system
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according to the present invention which is responsive to the load applied by
the
center section and wing sections to the ground is included.
Figure 2 is taken from US Patent 6,675,568 and shows the PRIOR
ART schematic top plan view of the header of Figure 1.
Figure 3 shows an isometric view from the rear and one side of one
embodiment of the header with the adapter removed and showing one embodiment
of the adjustment system of the present invention.
Figure 4 shows a rear view of the header with the adapter removed
and showing another embodiment of the adjustment system of the present
invention.
Figure 5 is a schematic illustration of the system logic of the apparatus
according to the present invention.
Figure 6 is a schematic illustration of the adjustment logic of the
apparatus according to the present invention.
DETAILED DESCRIPTION
Reference is made to US Patent 6,865,871 (Patterson) issued Mar. 15,
2005 which disclose details of an adapter for mounting a header on a combine
harvester, the disclosure of which may be referenced for more information.
Reference is also made to US Patent 6,675,568 (Patterson) issued
Jan. 13, 2004 which disclose details of a flexible header of the general type
with
which the present the disclosure of which may be referenced for more
information.
Figures 1 and 2 and part of the following description are taken from that
Patent for
Date Recue/Date Received 2023-08-22
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the convenience of the reader. Further details not included herein can be
obtained
by reference to that patent.
Reference is also made to US Patent 7,918,076 (Talbot) issued April 5,
2011 the disclosure of which may be referenced for more information which
disclose
in Figure 3 in rear elevational view a header 10 carried on an adapter 11 or
mounting assembly attached to the feeder house 12 of a combine harvester. In
Figure 1 the adapter is omitted for convenience of illustration.
The header 10 includes a frame 13 defined by a main rear beam 14
and a plurality of forwardly extending arms 15 which extend downwardly from
the
beam 14 and then forwardly underneath a table 16 which extends across the
header. At the forward end of the table 16 is provided a cutter bar 17. On top
of the
table 16 is provided a draper transport system 18 which carries the crop from
the
cutter bar across the header to a discharge location at the feeder house 12.
The
draper system 18 thus include two side drapers 18A extending from respective
ends
of the header inwardly toward the feeder house and a center adapter section
18B
which acts to feed the crop from the side drapers 18A rearwardly to the feeder
housing.
The header further includes a reel 19 including a beam on which is
mounted a plurality of reel bats (not shown) which are carried on the beam for
rotation with the beam around the axis of the beam. The beam is carried on
reel
support arms 19B which extend from the beam rearwardly and upwardly to a
support
bracket attached to the transverse main beam 14. The reel arms can be raised
and
Date Recue/Date Received 2023-08-22
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lowered by hydraulic cylinders 19D connected between the respective arm and
the
beam 14.
The above description of the header refers only schematically to the
construction since the details of the construction are well known to one
skilled in the
art.
Referring also to Figure 2, the adapter 11 comprises a frame 20 which
attaches to the feeder house 12 and carries at its lower end a pair of
forwardly
extending pivotal arms 21 which form respective first and second spring biased
lifting members and which extend forwardly underneath respective ones of the
frame
members 15 of the header. The pivotal arms 21 can pivot upwardly and
downwardly
about respective pivot pins 23 each independently of the other arm. Each arm
is
supported by a respective spring 24 attached to the respective arm 21. Thus
the
respective springs 24 provide respective first and second spring lifting
forces which
acts to pull up the respective arm 21 and provide a lifting force underneath
the
header at a lifting point partway along the respective frame member 15 and
underneath the draper 18 and the table 16.
At the center of the adapter is provided a link 26 which extends from
the frame 20 forwardly in the form of a hydraulic cylinder which allows
adjustment of
the length of the cylinder thus pivoting the header forwardly and rearwardly
about
the support point of the arms 21 on the underside of the header. Thus the
attitude of
the header, that is the angle of the table 16 to the horizontal can be tilted
by
operation of the cylinder forming the link 26.
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15
In addition the attitude of the header about an axis extending forwardly
of the direction of movement that is at right angles to the transverse beam 14
is
effected by the independent pivotal movement of the arms 21 provided by the
springs 24 which act as a floatation system. In addition the whole header can
float
upwardly and downwardly on the springs 24 with the link 26 pivoting to
accommodate the upward and downward movement and the arms 21 pivoting about
the respective pin 23.
The table 16 provides behind the cutter bar 17 a skid plate 16A which
is arranged to engage the ground. Thus upward force is provided from the
ground
which tends to lift the header taking weight off the support springs 24. In
practice the
springs are adjusted so that the springs act to support the majority of the
weight of
the header leaving a relatively small proportion of the weight to rest on the
ground.
Thus the header can float upwardly and downwardly as the ground provides areas
of
different height with one end of the header being movable upwardly
independently of
the other end by independent flexing of the springs 24. Thus the header tends
to
follow the ground level.
The beam 14 forms a main frame structure which is divided into a
number of separate pieces depending upon the number of sections of the header.
In
the embodiment shown there are three sections including a center section or
center
frame portion 10A, a first wing section or wing frame portion 10B and a second
wing
section or wing frame portion 10C. The center section 10A is mounted at the
adapter
so that the arms 21 extend into engagement with the center section. The wing
Date Recue/Date Received 2023-08-22
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sections are pivotally connected to the center section such that each can
pivot
upwardly and downwardly about a respective pivot axis generally parallel to
the
direction of movement.
The beam 14 is split into three portions each co-operating with a
respective one of the sections 10A, 10B and 10C and defining a main beam
therefor.
Each section of the beam 14 includes respective ones of the frame members 15
which support the respective portion of the table. Thus as best shown in
Figure 4,
there is a break 14A between the beam sections 14 of the center section 10A
and
one wing section 10B. The end most frame member 15A of the wing section 10B is
arranged at the break. The end frame member 15B of the center section 10A is
spaced inwardly from the break leaving space for a pivot coupling 27 extending
from
the frame member 15A to the frame member 15B and defining a pivot pin 27A
defining a first pivot connection lying on the pivot axis between the wing
section 10B
and the center section 10A.
The two sections 10A and 10B are supported each relative to the other
for pivotal movement of the wing section 10B about an axis extending through
the
pin 27A and through the break 14A so that the wing section is supported at its
inner
end on the center section but can pivot downwardly at its outer end so that
the
weight at the outboard end is unsupported by the center section and causes
downward or counter clockwise pivotal movement of the wing section 10B.
The wing section 10C is mounted in an identical or symmetrical
manner for pivotal movement about the other end of the center section 10A. The
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amount of pivotal movement allowed of the wing section relative to the center
section about the axis of the pivot pin 27A is maintained at a small angle
generally
less than 6 and preferably less than 4 as controlled by suitable mechanical
stop
members which are provided at a suitable location with the required mechanical
strength to support the wing frame section against upward or downward movement
beyond the stop members.
In one example, the outboard weight of the wing section 10B is
supported on a linkage 30 which communicates that weight from the inner end of
the
beam 14 of the section 10B through to the support for the center section 10A
at the
springs 24. The linkage is shown particularly in Figure 3 and includes a
tension link
31 extending from the inner end of the beam 14 to a bell crank 32 at the outer
end of
the center section 10A on the beam 14 together with a further compression link
33
which extends downwardly from the bell crank to a balance beam 34 located on
the
center section 10A at its interconnection with the arm 21.
The linkage operates to transfer the outboard weight of the wing
section inwardly to the center section and at the same time to balance the
lifting
force provided by the springs 24 so that it is proportionally applied to the
center
section and to the wing section.
The header is attached to the combine feeder house using the float
system described previously that supports the header so that it can be moved
up
when a vertical force about 1% to 15% of its weight is applied to the cutter
bar from
Date Recue/Date Received 2023-08-22
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the ground. The reaction of the float linkage that typically supports 85% to
99% of
the header weight on the header is used to balance the weight of the wings.
The system is designed so that if the operator sets the float so that the
float system supports 99% of the header weight then the remaining 1% will be
evenly distributed across the cutter bar. If the operator changes the float so
that 85%
is supported by the combine harvester then the remaining 15% is also evenly
distributed across the cutter bar without the operator making adjustments.
Thus, not
only is the total lifting force to each sections varied in proportion to the
total lifting
force but also that lifting force on each section is balanced across the width
of
section. As the sections are rigid between the ends, this requires that the
lifting
forces be balance between the ends to ensure the even distribution across the
cutter
bar of each section and thus of all the sections. This is achieved in this
embodiment
by a balancing system which includes a linkage connecting the force to the
wing
section and particularly the balancing beam 34. Thus the balance beam 34
balances
the lifting force applied to the ends of the center section relative to the
lifting force
which is applied to the outboard weight of the wing section so that the
lifting force is
even across the width of the header.
The inboard weight of the wing section is transferred through the pivot
27 to the outboard end of the center section and that weight is transferred
directly to
the balance beam 34. Also the outboard weight of the wing section is
transferred
through the link 31 and the bell crank 32 to the balance beam 34. Yet further
a lifting
force from the arm 21 is applied to the balance beam.
Date Recue/Date Received 2023-08-22
19
Thus reviewing Figures 3 and 4, the balance beam 34 is located above
the arm 21. The balance beam 34 has a forward end 34A which is pivotally
connected to the frame member 15 at a transverse pivot pin 34B. The arm 21
extends forwardly to a forward lifting point 21A which engages underneath a
forward
end 34A of the balance beam. Thus the lifting force from the arm 21 is applied
upwardly at the point 21A which is forward of the beam 14 and underneath the
table
16.
The balance beam 34 extends rearwardly from the forward end 34A
rearwardly to a rear end 34C to which is connected the compression link 33 at
a
bushing 33A. The compression link or compression member 33 thus applies an
upward pushing force which acts to support the outboard weight of the wing
section
and also applies some lifting force to the center section through the bell
crank 32.
The pivot pin 34B is attached to the center section so that some weight
from the center section, which is not carried on the bell crank, is
transferred to the
pivot pin and through that pin to the balance beam 34.
The lifting force from respective one of the first and second lift arms 21
is wholly applied at the respective one of the first and second lifting
positions 21A of
the balance beam. Thus these three forces are all applied to the balance beam
and
the balance beam acts to automatically proportion the forces relative to the
lifting
force.
Thus the support assembly includes a first component which is the pin
34B to provide a lifting force for the center frame portion. The support
assembly
Date Recue/Date Received 2023-08-22
20
which is the linkage includes a second component which is a tension link 33
arranged to provide a lifting force F2 for the outboard weight of the second
or wing
frame portion.
The whole support assembly including the balance beam 34, the lift
.. arm 21 and the springs 24 are arranged to provide a floating movement for
each of
the first and second frame portions that is the center and wing frame portions
relative to each other and relative to the propulsion vehicle such that upward
pressure from the ground on the skid element 16A which is greater in a
downward
force for a part of the weight of the header and supported by the lifting
force tends to
lift each of the center and wing frame portions relative to the propulsion
vehicle.
The balance beam 34 is arranged such that the first and second lifting
forces Fl and F2 are varied proportionally as the total lifting force FT is
varied. As
the force F2 includes the force lifting the wing section and a part of the
force lifting
the center section, this can be balanced relative to the lifting force Fl
which applies
a lifting force to the center section. The geometry of the balance beam and
the
linkage including the bell crank is arranged such that the balancing system
defined
thereby provides the lifting forces to the center section and wing section as
defined
above.
It will be noted that the linkage provided by the tension link 31,
compression link 33 and the bell crank 32 includes no spring connection and is
a
direct mechanical linkage so that the spring action or floating action of the
wing
section is provided by the spring 24.
Date Recue/Date Received 2023-08-22
21
The balance beam 34 extends parallel to the arm 21 so that the pivot
pins or bushings 34B and 33A have an axis at right angles to the balance beam
and
to the arm 21. The forces extend generally at right angles to the arm 21 since
the
arm 21 is generally horizontal underneath the header frame and underneath the
balance beam.
The bell crank 32 is located and supported on the beam 14 so that the
link 31 extends along the length of the beam 14 across the space 14A. Thus the
link
31 is located above the pivot 27A and communicates forces by tension.
The compression link 33 is pivotally attached to the bell crank at a
pivot connection pin 32B. The length of the arm 32C of the bell crank 32 can
be
adjusted by sliding the pin 32B along a slot 32D thus adjusting the mechanical
advantage of the bell crank to vary the mechanical advantage or moment of the
force F2 transferred to the outboard weight of the wing section. Thus the bell
crank
can be adjusted so that the forces Fl and F2 are balanced to produce
approximately
uniform contact pressure between the ground and the skid shoe. The bell crank
32 is
pivoted at pin 32E carried on a support 32F attached to the frame. The link 31
attaches to the bell crank 32 at the pin 32G.
It will be appreciated that the balance system using the balance beam
34 and the links 32 and 33 is merely one of many examples of design of balance
system which can be used.
Date Recue/Date Received 2023-08-22
22
In the system shown in the above patents and as manufactured and
sold by MacDon there is a requirement for the operator to periodically adjust
the
wing balance by adjusting the position of the pin 32B along the link 31.
According to the present arrangement, there is provided an adjustment
system one embodiment of which is shown in Figure 3 and is generally indicated
at
40. This arrangement 40 is arranged to provide adjustment automatically of the
balance system to maintain said balanced ground force distribution.
The adjustment system 40 includes a first sensor 41 at the pivot pin
27A to the left wing 10B and a second sensor (not visible) at the
corresponding pivot
pin of the second wing 10C. In this embodiment the sensors 41 are angle
sensors
mounted at the pin 27A which detect the angle of the wing 10B relative to the
center
portion 10A and any changes therein over time as the wing floats upwardly and
downwardly as described above.
Thus each sensor independently acts repeatedly, over a time period
during which the header is operating in said harvesting operation, to detect
the
changing positions of each wing frame portion relative to the center frame
portion.
The system 40 further includes a processor 42 arranged in response to
the positions sensed by the sensors to calculate a value representative of the
positions of the wing frame portions over a set time period.
Thus as shown in Figures 5 and 6, the processor 42 receives the
signals from the sensors 41 and independently records the left and right wing
positions determined by the angle sensor repeatedly, for example once per
second,
Date Recue/Date Received 2023-08-22
23
over a set period of time, for example 15 minutes. The processor then
calculates
from these signals an average value. These calculation are carried out only
when
the harvesting system is operating to avoid distorting the results from
stationary data
or data obtained when the header is not on the ground. A sensor 43 provides an
input indicative of header operation for example from the cutter bar.
Based on the difference of the average value calculated from the
nominal zero difference expected when the header is operating properly, the
processor accesses a look-up table to determine how much out of setting the
adjustment is presently determined to be. In response to this value from the
look up
table, an actuator 43 at the adjustment 32B is operated to move the adjustment
to
the newly determined proper location.
Thus in effect, the average values calculated allow the processor to
provide an indication as to whether the wing frame portions are predominantly
raised
or predominantly lowered during the time period. That is the wings will be
raised
and lowered at different times during operation depending on ground height but
the
average over a set time period should be zero.
For example the sensor 45 for detecting whether the header is
operating includes a knife speed sensor.
As two separate sensors are provided, one for each wing, this allows
the processor to use in calculation independent sensor data relating to the
independent positions of the wing frame portions to determine independent
adjustment values for the separate wing frame portions from the independent
sensor
Date Recue/Date Received 2023-08-22
24
data. However in some balance systems the wings may be adjusted as a common
single adjustment.
The processor and/or the look up table may provide an output such
that when the value is within a predetermined range of acceptability outside
of the
.. nominal zero value, no adjustment is made.
The processor also records the new adjustment positon after an
adjustment is effected. The processor can also halt the adjustment system to
allow
the operator to override the input values and re-set to a required operator
value.
The system can also be used to re-set to a factory default setting and can
include a
sub-program for sensor calibration.
For the factory default reset feature, the system will look up values
from a table which will set the flex linkage to a theoretically correctly
adjusted
position based on the header size and optional equipment. This feature is used
to
position the linkage where it should be theoretically and is intended for use
on initial
header setup and if issues arise during the auto adjust sequences. The factory
reset
is used as a starting point and continual refinement of the calibration is
done by the
system while the header is harvesting.
As shown in Figure 4 there is provided an alternative system 40A in
which the processor 42A receives signals from a series of height sensors 41A,
41B,
41C and 41D at ends of the wing portions 10A and 10C and at the ends of the
center portion 10A. These act to detect the height of the sensor and thus the
portion
on which it is mounted from the ground. In this way the system detects a
distance of
Date Recue/Date Received 2023-08-22
25
each of the wing frame portions and the center frame portion from a component
relative to which each of the portions moves, in this case the ground. Over
the
period of time, all three sections should statistically have the same average
distance
from the ground and any variation in this distance is indicative of the wings
being too
heavy or too light thus requiring an adjustment as set forth above.
As shown in Figure 1, there is provided a further alternative system in
which there is provided a plurality of separate ground engaging elements 50 at
spaced positions along the main frame structure 14 for supporting the cutter
bar
from the ground. Thus there are center elements 50 which generally support the
center section and wing elements which are mounted at or adjacent the outer
end of
each wing. Each element includes a load sensor 51 for providing an output
related
to a force applied by the header through the respective ground engaging
elements to
the ground. Thus the system operates, for detecting data relating to a
condition of
the balance system, by detecting a force applied by each of the wing frame
portions
.. and the center frame portion to the ground.
This data is then monitored over a selected time period and provides
information on the load applied by each of the sections to the ground which is
indicative of its position relative to the other sections. This data when
collected over
time can be used to generate a value for effecting the adjustment of the
balance
system.
This ground engaging elements can be formed by a wheel system or a
skid and are used as disclosed in US Patent 9,775,291 (Neudorf) issued October
3
Date Recue/Date Received 2023-08-22
26
2017 to support the header when cutting off the ground. The arrangement shown
in
Canadian Patent 2974643 filed July 27 2017 and published January 27 2019 can
also be used and the disclosures of these documents can be referenced for more
information.
Date Recue/Date Received 2023-08-22
