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Description  |
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TECHNICAL FIELD
This invention relates to apparatus for use on mobile machines with
outwardly extending portions. The invention is especially well suited for
use on mobile agricultural machines which have pivotally connected tool
bars or frame sections wherein one or more of the sections can be pivoted
upwardly away from the ground to an inactive, transport position.
BACKGROUND OF THE INVENTION AND
TECHNICAL PROBLEMS POSED BY THE PRIOR ART
Some conventional mobile agricultural machines are provided with two or
more frame sections or tool bars that are pivotally connected together
with a conventional hinge assembly that permits one frame section to pivot
or "float" relative to the other when the machine is being operated with
the frame sections in a lowered, ground-engaging position on uneven
terrain. This accommodates vertical variation in the terrain across the
width of the machine.
When a laterally extending frame section of such a machine is raised away
from the ground and folded back toward the adjacent section beyond a
certain angle--as when the machine is being prepared for transport along a
highway--the conventional hinge assembly permits the raised section to
freely fall a short distance toward the other frame section. This "free
fall" results in the machine being subjected to undesired impact loading.
It would be desirable to provide a folding implement frame section hinge
assembly with an improved construction which, in addition to accommodating
frame section float when a frame section is in the lowered,
ground-engaging position, would permit a frame section to be smoothly
raised and lowered. It would also be desirable if the improved hinge
assembly could prevent free fall of a raised frame section during the
folding and unfolding operations so as to avoid subjecting the machine to
undesired impact loading.
SUMMARY OF THE INVENTION
An improved implement floating hinge assembly is provided for accommodating
the folding of pivotally connected first and second frame sections. The
hinge assembly includes a first lever pivotally connected to the first
frame section, a second lever connected between the second frame section
and the first lever, and an extendable and retractable actuator pivotally
connected between the first frame section and the second lever. In the
improved assembly, the second lever is connected to the second frame
section about a pivot axis that is fixed relative to the second frame
section. A pin is movable with the second lever at a fixed distance from
the pivot axis of the connection between the second frame section and the
second lever. The first lever defines an elongated slot means for
receiving the pin to accommodate relative movement between the pin and the
first lever. With this arrangement, relative pivoting movement between the
frame sections can occur even after the frame sections have been unfolded.
Further, during the folding of the frame sections, the pin remains at one
end of the slot means so that a free fall of one of the frame sections
relative to the other does not occur. Numerous other features and
advantages of the present invention will become readily apparent from the
foregoing detailed description of the invention, from the claims, and from
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings forming part of the specification, in which
like numerals are employed to des like parts throughout the same,
FIG. 1 is a fragmentary, rear elevational view of a mobile machine
incorporating a conventional prior art floating frame hinge assembly for
accommodating the folding of pivotally connected first and second frame
sections;
FIG. 2 is a greatly enlarged, fragmentary, rear elevational view of the
right-hand rear portion of the machine illustrated in FIG. 1 showing the
hinge assembly with the frame sections in the lowered, ground-engaging
position;
FIG. 3 is a view similar to FIG. 2, but showing the conventional hinge
assembly moving toward the folded position;
FIG. 4 is a view similar to FIGS. 2 and 3, but showing the novel hinge
assembly of the present invention in operation to pivot or "fold" one of
the frame sections toward a raised, inactive position; and
FIG. 5 is a view similar to FIG. 4, but showing the hinge assembly of the
present invention in a fully folded position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Prior Art Design
Referring now to FIG. 1, a mobile machine is designated generally therein
by reference numeral 10. The machine 10 includes a working implement
comprising a central or main frame section 12 and pairs of frame sections
14 and 16 which laterally extend from either side of the central frame
section 12. The frame sections typically carry working tools such as those
associated with a planter, seed drill, etc. The machine 10 typically has a
plurality of wheels 18, as well as wheels 20 associated with the main
frame section 12, wheels 22 associated with the frame section 14, and
wheels 24 associated with the frame section 16.
In operation, the machine 10 is moved over the ground 26 with the frame
sections 14 and 16 in a lowered, ground-engaging position as illustrated
in FIG. 1. To accommodate road transport of the machine 10, the frame
sections are typically raised to an elevated, inactive position. To this
end, the frame section 16 may be pivoted or folded over on top of the
frame section 14 by means hereinafter described in detail so that the
frame section 16 is generally parallel to the first frame section 14. The
first frame section 14 can then be pivoted upwardly so that it is
approximately perpendicular to the main frame section 12 but is preferably
tilted a few degrees from the vertical towards the frame section 12.
As best illustrated in FIG. 2, each frame section 16 is pivotally connected
on an end of the frame section 14 about a pin 32. Each frame section 16 is
moveable between the raised, inactive position and a lowered,
ground-engaging position by an extendable and retractable actuator 34. In
the preferred embodiment illustrated, the actuator 34 is a dual acting
hydraulic cylinder-piston actuator. At one end, the actuator 34 is
pivotally connected to a portion of the frame 14, as at connection pin 36.
At the other end, the actuator 34 is pivotally connected by means of a pin
38 to first and second levers 41 and 42, respectively.
The first lever 41 is pivotally connected by means of a pin 46 to the frame
section 14, and the second lever 42 is attached to the frame section 16 by
means of a pin 48 carried on the frame section 16 and which is received in
a slot means or slot 50 defined in the second lever 42.
When the actuator 34 is in the extended position as illustrated in FIG. 2,
the frame section 16 is in the lowered, ground-engaging position, and the
pin 48 carried by the frame section 16 is positioned intermediate the ends
of the slot 50 in the second lever 42. The arrangement of the pin 48 in
the slot 50 permits the frame section 16 to pivot or "float" relative to
the frame section 14 when uneven terrain is encountered by the machine 10.
Relative pivoting movement between the frame sections is easily
accommodated because of the relative movement that is permitted between
the second lever 42 and the pin 48 in the elongated slot 50 of the lever
42.
When it is desired to raise the frame section 16 to the elevated or
inactive position, the actuator 34 is retracted. With reference to FIG. 2,
this causes the first lever 41 to pivot about pin 46 (counterclockwise as
viewed in FIG. 2). This also moves the second lever 42 relative to the pin
48. As the levers 41 and 42 are moved, the pin 38 necessarily first moves
upwardly in an arc, and this causes the lever 42 to be pulled upwardly so
as to cause the frame section 16 to be pivoted upwardly with the pin 48 at
the bottom end of the slot 50 in the second lever 42. The second lever 42
is under tension loading as this occurs.
Eventually, the frame section 16 is pivoted about pin 32 to the orientation
wherein the center of gravity of the frame section 16 is located on the
other side of the pin 32 (on the left side of the pin 32 as viewed in FIG.
3). At this point, the force of gravity acts to pull the frame section 16
downwardly in the counterclockwise direction around pin 32, and the pin 48
moves with the frame section 16 away from the end of the slot 50 (in the
direction of the arrow 60 illustrated in FIG. 3). The frame section 16,
and the pin 48 carried thereon, thus undergo a "free fall" until the pin
48 hits the other end of the slot 50. This causes an undesirable impact
loading on the machine 10.
It is to be noted that when the pin 48 initially slides away from the end
of the second lever slot 50, the tension loading on the lever 42 drops to
zero, and when the pin 48 impacts at the other end of the slot 50, the
loading on the second lever 42 becomes compressive. Continued retraction
of the actuator 34 effects continued movement of the second lever 42
(toward the left as viewed in FIG. 3), and the pin 48, owing to the weight
of the frame section 16, then moves with the lever 42 at the end of the
slot 50 until the pivoting action has been completed and the frame section
16 is substantially parallel to the frame section 14.
To unfold the frame sections, the actuator 34 is extended, and the frame
section 16 is pivoted back to the lowered, ground-engaging position. As
the center of gravity of the frame section 16 passes back to the other
side of the pivot pin 32, the frame section 16 again undergoes a "free
fall" as the pin 48 moves from one end of the second lever slot 50 to the
other end of the slot 50. This causes another impact loading on the
machine 10 as the loading on the second lever 42 changes from compression
to tension.
The conventional frame hinge assembly illustrated in FIGS. 2 and 3 may also
be employed with respect to the connection between the frame section 12
and the frame section 14 illustrated in FIG. 1. However, the frame section
14 would typically be pivoted to an inactive, elevated position relative
to the frame section 12 only after the frame section 16 had been folded
over relative to the frame section 14. Also, the frame section 14, with
the folded over frame section 16, would typically not be folded over
completely parallel to the frame section 12, but rather, would be pivoted
just slightly past the vertical.
The Improved Frame Hinge Assembly Of The Present Invention
FIGS. 4 and 5 illustrate the improved frame hinge assembly of the present
invention which is shown connecting a first frame section 14' and a second
frame section 16'. The first frame section 14' is pivotally connected to
the second frame section 16' about a pin 32' in the same manner as the
frame sections 14 and 16 described above with reference to FIGS. 1-3.
A first lever 41' is pivotally connected by means of a pin 46' to the first
frame section 14'. A second lever 42' is pivotally mounted about a fixed
axis by means of a pin 48' to the second frame section 16'. An extendable
and retractable actuator 34', such as an hydraulic cylinder-piston
actuator, is pivotally connected by means of a pin 36' to the first frame
section 14'.
There is a common connection of the first lever 41', the second lever 42',
and the actuator 34' to accommodate relative pivoting movements during
extension and retraction of the actuator 34'. The common connection
includes a pin 38' which is mounted for movement with the second lever 42'
at a fixed distance from the pivot axis defined by the pin 48' which
connects the second lever 42' to the second frame section 16'.
The pin 38' is received within an elongated slot 50' defined by the first
lever 41'. The pin 38' may be mounted to the assembly in a variety of
ways. The pin 38' may be journaled within both the end of the actuator 34'
and the end of the second lever 42'. On the other hand, the pin 38' may be
fixedly attached to the end of the second lever 42' and journaled within
the end of the actuator 34'. Alternatively, the pin 38' may be fixedly
attached to the end of the actuator 34' and journaled within the second
lever 42'. Also, the pin 38' may be separate from the pivotal connection
between the actuator 34' and the second lever 42'. However, in the
preferred embodiment illustrated, the actuator 34' is pivotally connected
to the second lever 42' about a pivot axis that is colinear with the
longitudinal axis of the pin 38'.
In the preferred embodiment illustrated in FIGS. 4 and 5, the elongated
slot 50' is defined, in part, by opposed straight side surfaces that are
parallel to, and equally distant from, a straight line extending between
the pin 38' and the connection of the first lever 41' to the first frame
section 14' at the pin 46'. Also, in the preferred embodiment, the width
of the elongated slot 50' is substantially equal to the diameter of the
pin 38' for accommodating the pin 38' in sliding engagement.
With the novel hinge assembly of the present invention, it is possible for
the frame sections 14' and 16' to be oriented in an unfolded, generally
coplanar orientation (similar to the orientation of the frame sections 14
and 16 of the prior art assembly illustrated in FIG. 2). In such an
orientation, the first lever 41' and the second lever 42' define an acute
included angle. In this unfolded orientation, the pin 38' is positioned
intermediate the ends of the slot 50' when the machine is on level ground.
The slot 50' thus permits relative movement between the pin 38' and the
first lever 41'. This accommodates relative pivoting movement or "float"
between the unfolded frame sections 14 and 16 when uneven terrain is
encountered.
When it is desired to raise the second frame section 16' to an inactive
position, the actuator 34' is retracted as illustrated in FIG. 4. This
results in the first lever 41' pivoting about the pin 46'. The pin 38' is
engaged by the first lever 41' at the bottom of the slot 50' and is
carried in an arc with the lever 41'. This subjects the second lever 42'
to tension and raises the lever 42' so as to pivot the second frame
section 16' about the main hinge pin 32'.
The novel hinge assembly of the present invention does not subject the
machine to impact loading when the frame section 16' is folded or raised
to the inactive position. As the frame section 16' is raised, the weight
of the frame section causes the pin 38' to exert a force on the first
lever 41' at the bottom of the slot 50'. The first lever 41' is thus
compressively loaded between the pin 38' and the pivot pin 46'. At the
position illustrated in FIG. 4, the center of gravity of the frame section
16' is directly over the main hinge pivot 32'. In FIG. 4, the center of
gravity force from the weight of the frame section 16' is schematically
illustrated by arrow 80'. Up to this point, the second lever 42' is in
tension, and beyond this point (as the frame section 16' pivots further in
the counterclockwise direction as viewed in FIG. 4), the second lever 42'
is in compression.
In FIG. 4, it is seen that the lines of action of the actuator 34' and
second lever 42' intersect at an obtuse angle A. As the frame section 16'
pivots further (counterclockwise as viewed in FIG. 4), the angle A
increases as the lines of action become colinear at an over center
position, and then the angle A becomes a reflex angle beyond the over
center position (FIG. 5).
Beyond the orientation illustrated in FIG. 4 but before the angle A becomes
a reflex angle, the pin 38' initially becomes subjected to a combined
force resulting from the compressive force in the second lever 42' and the
actuator 34'. This combined force on the pin 38' is directed toward the
top end of the elongated slot 50' in the first lever 41'. However, the
weight of the actuator 34' and the weight of the second lever 42', along
with frictional forces, maintain the pin 38' at the bottom of the
elongated slot 50'.
As the frame section 16' continues to pivot to the folded position
(counterclockwise as viewed in FIG. 5) and the angle A becomes a reflex
angle, the resulting force on the pin 38' from the second lever 42' and
the actuator 34' changes direction from toward the top of the slot 50' to
toward the bottom of the slot 50'. The pin 38' thus remains at the bottom
of the slot 50' during the frame folding sequence. The hinge assembly thus
permits the frame section 16' to be folded smoothly to the fully folded
position illustrated in FIG. 5 without any free fall impact loading of the
assembly.
The novel hinge assembly permits smooth unfolding of the frame sections
when actuator 34' is extended to reverse the above-described sequence.
However, if the frame sections are unfolded on ground that is not level,
there may be some slight free fall of the frame section 16' relative to
the frame section 14' around the mid-range position (such as illustrated
in FIG. 4). However, in this mid-range position, the elongated slot 50' in
the first lever 41' is almost perpendicular to the actuator 34' and to the
second lever 42'. Thus, any free fall will be minimal under such
conditions.
It will be readily observed from the foregoing detailed description of the
invention and from the illustrated embodiment thereof that numerous
variations and modifications may be effected without departing from the
spirit and scope of the novel concepts or principles of this invention.
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