U.S. patent application number 09/912651 was filed with the patent office on 2001-11-22 for breakaway for field marker on agricultural implement.
Invention is credited to Hundeby, David R..
Application Number | 20010042629 09/912651 |
Document ID | / |
Family ID | 4162975 |
Filed Date | 2001-11-22 |
United States Patent
Application |
20010042629 |
Kind Code |
A1 |
Hundeby, David R. |
November 22, 2001 |
Breakaway for field marker on agricultural implement
Abstract
A field marker for mounting on an agricultural implement
includes an elongated arm adapted to project outwardly laterally of
the implement when in its operating position and is adapted to
carry a field marking device at its outer distal end for making a
score mark on the ground. A mount for the arm at an inner proximal
end thereof allows pivoting of the arm about first and second
transverse axes whereby to allow the arm to swing upwardly and
downwardly about the first one of said axes when operating on
uneven ground while also allowing the arm to swing around the
second one of said axes from its outwardly projecting operating
position into another position. The arm includes inner and outer
arm sections secured together by a folding joint to permit the
inner and outer arm sections to be folded into juxtaposition with
one another and brought into the transport position. An extensible
actuator effects relative rotation of the inner and outer arm
sections, and a mechanism interacts with the inner and outer arm
sections and the actuator such that as the inner arm section is
pivoted through a selected angle, the outer arm section is pivoted
about said folding joint relative to the inner arm section. A
breakaway link on the arm permits the arm to swing as a whole
relative to the mount about the second axis away from its outwardly
projecting operating position when an obstacle is encountered and a
predetermined force on said arm has been exceeded. The breakaway
link has a resetting device associated therewith for returning the
arm to the operating position once the obstacle has been
cleared.
Inventors: |
Hundeby, David R.;
(Saskatoon, CA) |
Correspondence
Address: |
Larry W. Miller
New Holland North America, Inc.
500 Diller Avenue
P.O. Box 1895
New Holland
PA
17557-0903
US
|
Family ID: |
4162975 |
Appl. No.: |
09/912651 |
Filed: |
July 26, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09912651 |
Jul 26, 2001 |
|
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|
09428528 |
Oct 28, 1999 |
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Current U.S.
Class: |
172/266 ;
172/126; 172/624.5 |
Current CPC
Class: |
A01B 61/04 20130101;
A01B 69/024 20130101 |
Class at
Publication: |
172/266 ;
172/624.5; 172/126 |
International
Class: |
A01B 039/28 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 30, 1998 |
CA |
2,252,296 |
Claims
Having thus described the invention, what is claimed is:
1. A field marker for mounting on an agricultural implement,
comprising: an elongated arm adapted to project outwardly laterally
of the implement when in an outwardly projecting operating position
and being adapted to carry a field marking device at its outer
distal end for making a score mark on the ground; a mount for said
elongated arm at an inner proximal end thereof allowing pivoting of
said arm about first and second generally transverse axes such that
said elongated arm can swing upwardly and downwardly about said
first axis when operating on uneven ground while also allowing said
arm to swing around said second axis from its outwardly projecting
operating position into another position; and a breakaway link
pivotally connected to said mount and extending alongside said arm
to retain said arm in the operating position but which permits said
arm to swing relative to said mount about the second axis away from
the operating position when an obstacle is encountered by said arm
and a predetermined force on said arm has been exceeded, a
resetting device associated with said breakaway link to assist in
returning said arm to the operating position once the obstacle has
been cleared.
2. The field marker of claim 1 wherein said breakaway link extends
in general parallelism to said arm when said arm is in the
operating condition.
3. The field marker of claim 2 wherein said breakaway link extends
from a pivot point on said mount which is spaced from the second
axis to a pivot point associated with said arm, said breakaway link
including a pair of link members hinged together and adapted to
move from a slightly misaligned condition where the breakaway link
acts as a rigid link capable of withstanding compressive forces
arising from draft forces on said arm during normal operation
whereby to inhibit the arm from swinging about the second axis on
said mount to a collapsed condition corresponding to a breakaway
position of the arm after an obstacle has been encountered.
4. The field marker of claim 3 wherein said resetting device
comprises a biasing device which tends to hold the breakaway link
members in the slightly misaligned condition until the
predetermined force has been exceeded whereby the collapsed
condition of the breakaway link members occurs.
5. The field marker of claim 4 including adjustment means for
varying the degree of misalignment between said breakaway link
members whereby to enable the force causing breakaway to be
predetermined.
6. The field marker of claim 1 wherein said breakaway link includes
a compressible member which compresses when the predetermined force
has been exceeded to permit swinging of the arm away from the
operating position.
7. The field marker of claim 6 wherein the compressible member
includes a pair of telescoping members having a compression spring
thereon to bias said members in directions away from one
another.
8. The field marker of claim 7 wherein said arm includes inner and
outer arm sections secured together by a folding joint to permit
said inner and outer arm sections to be folded and brought into the
transport position.
9. The field marker of claim 8 including an actuator for effecting
the folding about said folding joint of said inner and outer arm
sections into and out of the transport position, said actuator also
holding said inner and outer arm sections in general alignment as
the arm is swung away from its operating position when an obstacle
is encountered.
10. The field marker of claim 9 wherein said folding joint includes
a crank arm and a fold link associated therewith, said breakaway
link extending from said pivot point on said mount in spaced
generally parallel relation to said inner arm section to a pivot
point on said crank arm, with the crank arm and fold link being
adapted to cooperate with the breakaway link such that, as said
inner arm section is rotated, said outer arm section rotates
relative thereto.
11. The field marker of claim 10 wherein said actuator is connected
between said inner arm section and said crank arm whereby extension
and retraction of said actuator effects rotation of the crank arm
relative to said inner arm section and at the same time by virtue
of the interaction between the linkages defined by said breakaway
link, crank arm, mount and inner arm section effects the rotation
of the inner arm section relative to said mount.
12. The field marker of claim 1 further comprising: a biasing
device acting between said mount and said arm to apply lifting
forces to the arm whereby the field marking device is provided with
the required degree of total down force as to enable a suitable
score mark to be made.
13. In an agricultural implement for working the surface of the
ground and having a frame adapted for movement over the ground;
ground working devices mounted on said frame; and a field marking
apparatus for making a score mark on the ground including an
elongated arm adapted to project outwardly laterally of the
implement when in an outwardly projecting operating position and
being adapted to carry a field marking device at an outer distal
end for making a score mark on the ground, a mount for said
elongated arm at an inner proximal end thereof allowing pivoting of
said arm, and a breakaway link pivotally connected to said mount
and extending alongside said arm to retain said arm in the
operating position but which permits said arm to swing relative to
said mount about the second axis away from the operating position
when an obstacle is encountered by said arm and a predetermined
force on said arm has been exceeded, the improvement comprising:
said breakaway link having a resetting device associated therewith
to assist in returning said arm to the operating position once the
obstacle has been cleared.
14. The agricultural implement of claim 13 wherein said mount
permits pivoting of said arm about first and second generally
transverse axes such that said elongated arm can swing upwardly and
downwardly about said first axis when operating on uneven ground
while also allowing said arm to swing around said second axis from
its outwardly projecting operating position into another
position.
15. The agricultural implement of claim 14 wherein said breakaway
link extends from a pivot point on said mount which is spaced from
the second axis to a pivot point associated with said arm, said
breakaway link including a pair of link members hinged together and
adapted to move from a slightly misaligned condition where the
breakaway link acts as a rigid link capable of withstanding
compressive forces arising from draft forces on said arm during
normal operation whereby to inhibit the arm from swinging about the
second axis on said mount to a collapsed condition corresponding to
a breakaway position of the arm after an obstacle has been
encountered.
16. The agricultural implement of claim 15 wherein said resetting
device comprises a biasing device which tends to hold the breakaway
link members in the slightly misaligned condition until the
predetermined force has been exceeded whereby the collapsed
condition of the breakaway link members occurs.
17. The agricultural implement of claim 16 including adjustment
means for varying the degree of misalignment between said breakaway
link members whereby to enable the force causing breakaway to be
predetermined.
18. The agricultural implement of claim 15 wherein said breakaway
link includes a compressible member which compresses when the
predetermined force has been exceeded to permit swinging of the arm
away from the operating position.
19. The agricultural implement of claim 18 wherein the compressible
member includes a pair of telescoping members having a compression
spring thereon to bias said members in directions away from one
another.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to a field marker for mounting on an
agriculture implement to generate a marked line on the ground
indicative of the path of the implement.
[0002] Field markers are commonly used on farming implements to
score a mark outward from one side of an implement when making an
operating pass so that the mark may act as a directional guide to
the operator on a subsequent pass. Folding field markers are also
common so that long arms may be compactly folded inward to the
implement for more compact transportation between operating
locations.
[0003] An example of a folding field marker is shown in U.S. Pat.
No. 5,027,525, issuing to Haukass, which shows a bi-fold field
marker having a device which automatically folds the outer arm to
lie along the inner arm when an actuator acts on the inner arm to
fold it inward to the implement on which it is mounted. This
particular field marker is also exemplary of the incorporation of a
breakaway device which allows the arm to fold rearwardly when it
encounters an obstacle. The spring of this breakaway device
includes a spring serving two functions, one being to provide
resetting force for the break action provided by a cradle, the
other being to serve as a down force biasing means. The spring
provides bias to relieve some of the weight of the marker arm to
vary the downward force with which the end of the marker scores the
ground. The spring of the Haukaas patent, depending on soil
hardness or other variables, can be difficult to adjust to give the
most desirable combination of resetting force and down force. It is
known that the design disclosed in the Haukaas patent is often
manufactured with a shear pin to retain the marker in the field
position and which must be replaced after a breakaway action
occurs; otherwise the resetting spring is not able to return and
maintain the arm in the operating position.
[0004] The Haukaas design has a mount structure with two members
connected by a horizontal pivot to allow the outer end of the
marker arm vertical movement relative to the implement over uneven
ground. An additional member, a cradle, is provided with a vertical
joint to allow a breakaway action.
SUMMARY OF THE INVENTION
[0005] It is an object of this invention to provide a field marker
with an automatically re-setting breakaway mechanism.
[0006] It is a feature of this invention that the field marker
allows for independent setting of breakaway resetting force and
down force biasing.
[0007] It is still another object of this invention to improve the
action of the folding arm in a folding field marker.
[0008] It is an advantage of this invention to provide a mounting
for a field marker that is manufactured with fewer parts than
previously known in the prior art.
[0009] A field marker for mounting on an agricultural implement in
accordance with one aspect of the invention includes an elongated
arm adapted to project outwardly laterally of the implement when in
its operating position and being adapted to carry a field marking
device at its outer distal end for making a score mark on the
ground, a mount for said arm at an inner proximal end thereof
allowing pivoting of said arm about first and second generally
transverse axes whereby to allow the arm to swing upwardly and
downwardly about the first one of said axes when operating on
uneven ground while also allowing said arm to swing around the
second one of said axes from its outwardly projecting operating
position into another position; and a breakaway link pivotally
connected to said mount and extending alongside said arm to retain
said arm in the operating position but which permits said arm to
swing relative to said mount about the second axis away from its
outwardly projecting operating position when an obstacle is
encountered and a predetermined force on said arm has been
exceeded, said breakaway link having a resetting device associated
therewith to assist in returning said arm to the operating position
once the obstacle has been cleared.
[0010] The breakaway link preferably extends in general parallelism
to said arm when the latter is in the operating condition.
[0011] In one embodiment the breakaway link extends from a pivot
point on said mount which is spaced from the second axis to a pivot
point associated with said arm, said breakaway link comprising a
pair of link members hinged together and adapted to move from (a) a
slightly misaligned condition where the breakaway link acts as a
rigid link capable of withstanding compressive forces arising from
draft forces on said arm during normal operation whereby to inhibit
the arm from swinging about the second axis on said mount to (b) a
collapsed condition corresponding to a breakaway position of the
arm after an obstacle has been encountered.
[0012] The above-noted resetting device typically comprises a
biasing device which tends to hold the breakaway link members in
the slightly misaligned condition until the predetermined force has
been exceeded and the collapsed condition of the breakaway link
members occurs.
[0013] Adjustment means may be provided for varying the degree of
misalignment between said breakaway link members whereby to enable
the force causing breakaway to be predetermined.
[0014] In another embodiment the breakaway link may include a
compressible member which compresses when the predetermined force
has been exceeded to permit swinging of the arm away from its
operating position. The compressible member preferably includes a
pair of telescoping members having a compression spring thereon to
bias said members in directions away from one another.
[0015] The field marker arm typically includes inner and outer arm
sections secured together by a folding joint to permit said inner
and outer arm sections to be folded and brought into the transport
position. An actuator is preferably provided for effecting the
folding about said folding joint of said inner and outer arm
sections into and out of the transport position, said actuator also
holding said inner and outer arm sections in general alignment as
the arm is swung away from its operating position when an obstacle
is encountered.
[0016] The folding joint in one embodiment includes a crank arm and
a fold link associated therewith and wherein said breakaway link
extends from said pivot point on said mount in spaced generally
parallel relation to said inner arm section to a pivot point on
said crank arm, with the crank arm and fold link adapted to
cooperate with the breakaway link such that as said inner arm
section is rotated, said outer arm section rotates relative
thereto.
[0017] Preferably said actuator is connected between said inner arm
section and said crank arm whereby extension and retraction of said
actuator effects rotation of the crank arm relative to said inner
arm section and at the same time by virtue of the interaction
between the linkages defined by said breakaway link, crank arm,
mount and inner arm section effects the rotation of the inner arm
section relative to said mount.
[0018] The field marker preferably includes a biasing device acting
between said mount and said arm to apply lifting forces to the arm
whereby the field marking device is provided with the required
degree of total down force as to enable a suitable score mark to be
made.
[0019] The preferred embodiment of the present invention has a
simplified marker arm mounting structure having only two main
members. The marker arm is connected to the second member on a
generally vertical axis to allow folding and unfolding of the
marker arm. In the present embodiment this same vertical axis also
provides for the breakaway action. The second member is attached to
a first member directly on a horizontal axis. This allows the
second member to pivot about the first member, and allows the outer
end of the marker arm vertical movement when operating over uneven
ground. In the transport position the vertical axis is held
generally vertical or slightly inclined inwardly. In the operating
position, the vertical axis is slightly inclined outwardly.
[0020] A field marker for mounting on an agricultural implement in
accordance with another aspect of the invention includes an
elongated arm adapted to project outwardly laterally of the
implement when in its operating position and being adapted to carry
a field marking device at its outer distal end for making a score
mark on the ground, a mount for said arm at an inner proximal end
thereof allowing pivoting of said arm about first and second
generally transverse axes whereby to allow the arm to swing
upwardly and downwardly about the first one of said axes when
operating on uneven ground while also allowing said arm to swing
around the second one of said axes from its outwardly projecting
operating position into a transport position; said arm including
inner and outer arm sections secured together by a folding joint to
permit said inner and outer arm sections to be folded into
juxtaposition with one another and brought into the transport
position, an actuator mounted to said inner arm section for
effecting rotation of said inner and outer arm sections, and a
mechanism interacting between said mount and said inner and outer
arm sections and connected to said actuator such that as said inner
arm section is pivoted by said actuator through a selected angle
relative to said mount, said outer arm section is pivoted about
said folding joint through an angle relative to said inner arm
section substantially greater than the extent of said selected
angle.
[0021] The above-noted mechanism in a preferred form of the
invention is adapted to effect pivoting of said outer arm section
through an angle approximately twice the extent of the angle
through which said inner arm section pivots.
[0022] The mechanism noted above preferably includes an elongated
link extending generally parallel to said inner arm section from
said mount, and a crank arm pivotally connected between distal end
portions of the inner arm section and said elongated link, said
crank arm being linked to said outer arm section, and said actuator
being connected such that as it extends and retracts said crank arm
is rotated and said inner and outer arm sections are caused to
pivot relative to one another.
[0023] These and other objects, features and advantages can be
accomplished according to the instant invention by providing a
field marker for mounting on an agricultural implement, the field
marker including an elongated arm adapted to project outwardly
laterally of the implement when in its operating position and being
adapted to carry a field marking device at its outer distal end for
making a score mark on the ground. A mount for the arm at an inner
proximal end thereof allows pivoting of the arm about first and
second transverse axes whereby to allow the arm to swing upwardly
and downwardly about the first one of said axes when operating on
uneven ground while also allowing the arm to swing around the
second one of said axes from its outwardly projecting operating
position into another position. The arm includes inner and outer
arm sections secured together by a folding joint to permit the
inner and outer arm sections to be folded into juxtaposition with
one another and brought into the transport position. An extensible
actuator effects relative rotation of the inner and outer arm
sections, and a mechanism interacts with the inner and outer arm
sections and the actuator such that as the inner arm section is
pivoted through a selected angle, the outer arm section is pivoted
about said folding joint relative to the inner arm section. A
breakaway link on the arm permits the arm to swing as a whole
relative to the mount about the second axis away from its outwardly
projecting operating position when an obstacle is encountered and a
predetermined force on said arm has been exceeded. The breakaway
link has a resetting device associated therewith for returning the
arm to the operating position once the obstacle has been
cleared.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The advantages of this invention will be apparent upon
consideration of the following detailed disclosure of the
invention, especially when taken in conjunction with the
accompanying drawings wherein:
[0025] FIG. 1 is a top plan view of a field marker incorporating
the principles of the present invention, the field marker is
depicted in an operational position;
[0026] FIGS. 2A, 2B and 2C are top plan views of the inner, middle
and outer portions respectively of the field marker as shown in
FIG. 1;
[0027] FIGS. 3a and 3b are top plan views respectively of the field
marker as the marker arm swings away after encountering an
obstacle;
[0028] FIG. 4 is an enlarged view showing the relative position of
the various components following the breakaway action;
[0029] FIGS. 5a, 5b and 5c are top plan views showing the field
marker being folded up from its extended operating position into a
folded position alongside an agricultural machine for
transport;
[0030] FIG. 6 is a perspective view of the field marker in the
fully folded transport position;
[0031] FIG. 7 is a top view of a modified version of the field
marker in operating position;
[0032] FIG. 8 is a top view of the modified field marker showing a
close up view of the compression spring in operating position;
[0033] FIG. 9 is a top view of the modified field marker in a
partial breakaway position;
[0034] FIG. 10 is a top view of the modified field marker showing a
close up view of the compression spring in a partial breakaway
position;
[0035] FIG. 11 is a top view of the disk end of a field marker
having a shield or fender thereon and with the disk positioned to
provide a less aggressive mark in accordance with a further aspect
of the invention; and
[0036] FIG. 12 is a top view of the disk end of the field marker
with the disk positioned to provide a more aggressive mark.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0037] An agricultural implement 10 is shown with the field marker
12 attached to it. The marker 12 has a mounting structure for
attaching it to the implement. The mount structure comprises two
main members 14 and 16. The mount member 14 attaches the marker to
the implement and mount member 16 is attached to mount member 14
via a generally horizontal pivot shaft 18. The marker has an
elongated arm generally designated 20. The arm is comprised of two
sections: an inner arm section 22 is attached at one end to mount
member 16 via a generally vertical pivot joint 25, and an outer arm
section 24 is pivotally attached at one end to the second end of
the inner arm section 22 via a folding joint 26. A ground engaging
element 28 is attached to the distal end of the outer arm section
24 for scoring a mark in the field when operating.
[0038] In operating position the marker inner and outer arm
sections 22, 24 are held generally aligned and are extended
laterally outward from the implement by rotating the arm 20 about
the vertical pivot shaft 24 so that the marker arm 20 is generally
transverse to the director of travel for scoring a mark on the
ground to the side of the implement as the implement moves across
the field.
[0039] As the implement moves across the ground, the marker arm can
pivot about the horizontal pivot shaft 18 so the outer end of the
arm can move vertically relative to the implement. This
accommodates variations in ground elevation between the implement
and the outer end of the marker, so that the ground element 28 is
allowed to follow uneven ground surfaces.
[0040] A coil tension spring 30 extending between an adjustable
anchor on mount 14 and the mount member 16 provides bias to raise
the arm 20 upwardly, relieving some of the weight of the arm from
the ground element 28. The tension in spring 30 is adjustable so
the down force on the ground element resulting from the weight of
the marker arm 20 can be adjusted. Alternately this bias force can
be provided by a hydraulic actuator acting under controlled
pressure, possibly with use of a pressure reducing-relieving valve,
and possibly in combination with soil hardness sensing.
[0041] The marker arm 20 may be folded toward the implement so it
is more compact for transport. The spring 30 biases mount member 16
relative to mount member 14 about the horizontal axis of shaft 18.
As the marker is folded, it's center of gravity is brought closer
to this horizontal axis and the spring 30 begins to support the
marker clear of the ground and keeps it in a raised position when
it is fully folded for transport. As the marker is being extended,
the spring 30 keeps the marker clear of the ground until it has
been substantially extended.
[0042] The outer arm section 24 is folded relative to the inner arm
section 22 by the action of folding crank 32 which is pivotally
connected at pivot 33 near the distal end of the inner arm section
22 at a distance offset from the folding joint 26. A fold link 34
is pivotally connected at one end 36 to another point on the crank
32, and at it's second end is pivotally connected to the outer arm
section 24 at a pivot point 38 offset from the joint 26. An
actuator 40 is connected between the inner arm section 22 and the
crank 32 and is controlled to rotate the crank. The crank 32 and
fold link 34 arrangement acts to fold or unfold the outer arm
section 24 relative to the inner arm section 22 through a range of
about 180 degrees when the crank 32 is operated by the
actuator.
[0043] A breakaway link generally designated 42 is also pivotally
connected to the crank 32, link 42 extending substantially parallel
to inner arm section 22. Pin 44 by which the actuator 40 is
connected to the crank provides a convenient pivotal connection for
the link 42. It is not required that they are connected at the same
point; however the connection point is selected so that the
geometry of the parallel breakaway link 42 in combination with the
arrangement of the crank 32 and fold link 34 causes the inner arm
section 22 to rotate through a range of about 90 degrees, when the
outer arm section 24 is folded 180 degrees. The parallel breakaway
link 42 is therefor also pivotally connected to the mount member 16
at pivot point 45 offset from pivot joint 25 by a selected amount
which causes the action described above. Various combinations of
offsets between the pivot joints of the parallel link, crank, fold
link, and arm sections can be selected for a similar resulting
folding motion.
[0044] The parallel breakaway link 42 is constructed of an inner
link 42a and an outer link 42b, pivotally connected to each other
at one end by a joint 50. The inner or proximal end of the inner
link 42a is connected to mount member 16 at pivot 45 as described
previously. The distal end of the outer link 42b is connected to
the crank 32 as described previously. The breakaway link members
42a, 42b are biased toward substantial straight alignment; however
the joint 50 between them is maintained slightly offset of a
straight line between pivot joints 44 and 45, to the side opposite
of the marker arm 20.
[0045] During operation, draft forces against the end of the marker
arm 20 result in compressive forces in the parallel breakaway link
42. Since the joints are slightly misaligned as described above,
the compressive force causes resulting reaction couples at joints
44, 45, and 50 which would tend to cause breakaway link members
42a, 42b to fold about joint 50. Outer link 42b has an extension 43
on it's first end to which a resetting tension spring 52 is
attached at point 54. The resetting spring 52 is also attached to
the inner link 42a via a threaded tension adjusting eye bolt 56.
The attachment points are arranged so that the resetting spring 52
produces a biasing moment about joint 50 which opposes the folding
couples. The outer link 42b is also provided with an abutment 58 at
its inner end,. The inner link 42a has a corresponding abutment 60,
which rests on abutment 58 when the outer and inner breakaway links
42a, 42b are in operational alignment, and maintains a selected
amount of misalignment between the joints 44, 45 and 50. The
abutment 60 is made adjustable by a threaded stud so that the
offset of joint 50, when the link members 42a, 42b are in
operational alignment, can be set to provide the desired breakaway
force. The threaded adjustment bolt 56 as described above enables
adjustment of the tension of resetting spring 52 for additionally
setting the breakaway force and also for setting the resetting
force.
[0046] The breakaway link members 42a, 42b will fold or collapse
about joint 50 when the breakaway threshold is exceeded and the
marker arm 12 will fold rearwardly about joint 24. During breakaway
folding the marker arms sections 22, 24 are maintained in alignment
by the actuator 40 and folding joint 26, which are not affected by
the breakaway action. The present embodiment thus allows the arm to
swing back, away from an obstacle, rather than wrap around an
obstacle, (and without need for a third mount member) to allow for
the breakaway action.
[0047] The force of the resetting spring 52 can be set
independently of the down force biasing spring 30. The resetting
spring can be set with enough force so that the marker resets
automatically in many instances.
[0048] One skilled in the art will recognize that the fold
actuator, as described above, does not restrict the breakaway
action. Furthermore, the parallel link arrangement for folding the
inner and outer arms of the marker is more reliable than the cable
arrangement of certain prior art designs in which there can be slip
between components. When the outer end of the marker arm is
naturally being raised from the ground, as the marker arm rotates
back in a breakaway manner because the axis it rotates about is
inclined, the marker rotates in a plane inclined from
horizontal.
[0049] Additional Embodiments and Variations
[0050] In another embodiment of the invention, the parallel
breakaway link has a compressible section rather than a pivotal
joint. In this design the spring bears all of the breakaway
force.
[0051] A modified field marker is shown in FIGS. 7-10. This marker
is much the same as described and shown in FIGS. 1-6. However, the
folding breakaway link 42 has been replaced with a telescoping
spring-biased breakaway link 60. The parallel breakaway link
arrangement 60 includes two telescoping members 62 and 64, and coil
compression spring 66. Spring 66 is joined to two annular mounting
plates 68 and 70; with mounting plate 68 being located on member 62
and mounting plate 70 being located on member 64.
[0052] When the field marker is traveling in soil in the direction
indicated and an obstruction is encountered, the breakaway system
will collapse the marker arm to allow it to swing back and pass the
obstruction as seen in FIGS. 9 and 10. Member 64 is sized to
telescope in and out of member 62. When the obstruction creates a
force on the field marker in the direction opposite the direction
of travel, member 64 telescopes into member 62. To allow this to
occur, spring 66 must compress as the two mounting plates are
pushed closer together.
[0053] As the members telescope to shorten the overall length of
the parallel breakaway link 60 and the spring compresses, the
entire parallel link system will pivot about vertical axes 24 and
45. In this way, the field marker is able to swing back until the
obstacle is passed. When the obstacle has been passed and the force
in the direction opposite the direction of travel has been removed,
spring 66 will push the mounting plates 68, 70 apart and with it,
push member 64 out of member 62. The parallel link system will
pivot about points 24 and 25 to the full operating position again
as shown in FIG. 7.
[0054] Although this embodiment is shown in conjunction with
bi-fold markers, it also has applications for tri-fold markers. For
example, a tri-fold marker could have an inner section pivotally
attached to the implement frame. The mount structure 14, 16 would
be located at the distal end of the inner arm section. During
breakaway, the marker arm outer portion(s) would swing back about
the vertical pivot axis defined by the mount as described
previously but the inner arm section would remain fixed and act in
effect as an extension of the implement frame.
[0055] Another aspect of the invention is concerned with the fact
that as field markers travel through the soil, they frequently
encounter obstacles. Obstacles such as tree branches can easily get
wedged between the disk at the end of the arm and the disk mounting
plate. Thus, then, the rotation of the disk can be hindered and a
proper marking in the ground may not be formed.
[0056] Another frequent problem with field marker disks is that of
adjusting the angle of the disk with respect to the direction of
travel. The angled position of the disk dictates whether the mark
left in the field is more aggressive or less aggressive.
[0057] Therefore, the objectives of this aspect of the invention
are to provide a shield or fender giving smooth transition from the
outer arm of a field marker to the marker disk to allow the disk to
slip cleanly off any obstacles encountered, to provide means of
simplifying the disk angle adjustment and to provide means to
maintain the smooth transition from the outer arm to the disk
throughout the entire range of angle adjustment.
[0058] Referring now to FIGS. 11 and 12, this embodiment of the
field marker arm 100 has mounting plate 102 at the end of the
marker arm. Shaft 103 rotatably mounts the coulter disk 105. Shaft
103 is seated in a shield or fender 104 bolted to the mounting
plate 102. The fender 104 (made from steel plate) provides a smooth
transition from the mounting plate 102 to the disk 105. The fender
104 in essence only has to be located to the side facing the
direction of travel. Having the fender located on the backside of
the field marker is not necessary in order to keep debris from
being caught in the marker. However, a feature of the specific
field marker described above is that it can be mounted on either
side of the implement. Having a symmetrical fender that is located
on both sides of the disk would allow the marker to be used on
either side of the implement.
[0059] The fender 104 is of simple construction and provides a pair
of arms 108 which extend out from the mounting plate 102 with the
arms 108 having sloping shoulder portions 109 curving smoothly
around toward their distal ends 112 to embrace diametrically
opposed edge portions of the disc. The distal ends are notched at
110 to receive the disc edge portions loosely therein so as not to
interfere with the disc rotation.
[0060] By virtue of the smooth shape of the fender 104 debris
encountered in the field tends to slide along the shoulders 109 and
off the arms of the fender thus avoiding fouling of the disc
105.
[0061] Fender 104 also includes two arcuate slots 107 that receive
bolts 106 on the mounting plate 102. This mechanism allows for very
easy angle adjustment. The bolts simply are loosened, the angle
adjusted and bolts re-tightened. FIG. 11 shows the orientation of
the disk for a less aggressive mark while FIG. 12 shows the
orientation of the disk for a more aggressive mark.
[0062] This fender mount system can be implemented on a field
marker of any configuration and any folding sequence.
[0063] It will be understood that changes in the details,
materials, steps and arrangements of parts which have been
described and illustrated to explain the nature of the invention
will occur to and may be made by those skilled in the art upon a
reading of this disclosure within the principles and scope of the
invention. The foregoing description illustrates the preferred
embodiment of the invention; however, concepts, as based upon the
description, may be employed in other embodiments without departing
from the scope of the invention.
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