Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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APPLICATION FOR PATENT
of
LARRY P. ROBINSON
for
MULTIPLE IMPLEMENT TOW BAR ASSEMBLY
HILL & SCHUMACHER
335 BAY STREET
SUITE 802
TORONTO, ONTARIO
CANADA, M5H 2R3
(416) 368-1097
CA 02242449 1998-07-07
MULTIPLE IMPLEMENT TOW BAR ASSEMBLY
BACKGROUND OF THE INVENTION
Field of the invention
This invention is generally directed to agricultural
implement tow bars of the type which enable a plurality of
implements to be pulled by a single tractor and, more
particularly, to a tow bar assembly having adjustable outrigger
beams from at least one has a dolly connected thereto to which an
implement, such as a hay baler, may be selectively hitched in such
a manner as to enable the implement to track the natural contour
of the ground over which the implement passes. The tow bar
assembly is further of the type which allows the lateral spacing
between the implements to be altered during movement through a
field to adjust for spacing of windrows, and to facilitate over-
the-road transport and vehicle turning.
HISTORY OF THE RELATED ART
After hay and other vegetable matter has been cut and/or
processed in the field, it is normally raked into windrows for
purposes of facilitating baling of the material into either round
or rectangular bales. Conventionally, a single hay baler is
pulled through a field by a tractor or similar vehicle with the
hay baler passing over a single windrow at a time. This requires
repeated passes of the tractor through the field, thereby
consuming not only fuel but also requiring multiple hours of
vehicle operation and operator worktime.
In some agricultural environments, it has been proposed to
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utilize multiple implements pulled by a single tow bar to increase
the rate of harvesting. By way of example, in U.S. Patent
5,099,635 to Butkovich et al., a system for harvesting cotton is
disclosed in which a tow bar assembly is provided for
simultaneously carrying a plurality of cotton harvesting units.
In U.S. Patent 3,437,152 to Barrentine, an agricultural implement
for pulling stalks, such as corn stalks from which corn has been
harvested, is disclosed for pulling and grinding the stalks of
multiple rows of the stalks simultaneously.
Another example of agricultural implement incorporating
multiple cutting units is disclosed in U.S. Patent 4,304,086 to
Stuchl wherein a lawnmowing attachment has a plurality of
lawnmowing decks which are mounted in laterally spaced
relationship with respect to one another in order to maximize the
cutting width as the implement passes over an area being mowed.
There is an ever-increasing need to reduce costs associated
with the baling of hay and other forage products. By enabling a
plurality of farm implements, such as baling machines, to be
operated simultaneously, not only is it possible to reduce man
hours associated with the baling but the operating hours of the
harvesting machinery would be considerably reduced, especially
with respect to the powering units, such as tractors, which will
effectively extend the overall life of such vehicles.
It should be noted at this point in this application that the
term "hay baler" is utilized. It should be noted that "balers"
are also conventionally used for baling other forage materials
such as peanut vines and the like which are acceptable as fodder.
The term "hay baler" is meant to be generic to all types of balers
having the features which are described herein with respect to the
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Description of the Preferred Embodiment and are not limited to hay
balers per se.
In applicant's co-pending U.S. application referenced above,
a tow bar assembly for multiple hay balers is disclosed which
enables up to three separate hay balers to be pulled by a single
tow bar having a pair of pivotable outrigger beams associated
therewith. The tow bar assembly further includes a hydraulic
system which allows a plurality of pumps to be mounted thereon
which are used to drivingly engage the drive inputs to each of the
balers which are hitched to the tow bar assembly. In this manner,
up to three hay balers may be powered and pulled by a single
tractor in such a manner that the lateral spacing between the
balers may be varied as they are pulled through a field or as
required to facilitate turning at the end of rows and for further
facilitating transport of the balers on conventional roadways.
The tow bar assembly is particularly adapted for use with smaller
hay balers of the type which require a drive input from a power
source and are therefore normally smaller and lighter in weight
than many self-powered hay balers which are currently in use in
many areas. Conventional self-powered round hay balers weigh in
excess of a ton and, when the additional weight of hay being
rolled within the balers is added to the gross weight of the
implement as it is pulled through the field, the load imparted to
an implement hitch tongue becomes significant and generally
prohibits the use of outrigger beams which are designed to permit
only horizontal or lateral movement of an implement during use.
In view of the foregoing, there remains a need to provide a
tow bar assembly for use with a plurality of implements, such as a
plurality of self-powered hay balers, which enables the larger and
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heavier self-powered implements to be effectively pulled through a
field utilizing a single tow bar assembly.
SUMMARY OF THE INVENTION
The present invention is directed to a tow bar assembly for
use with tractors or other vehicles for enabling a plurality of
agricultural implements, such as hay balers, to be simultaneously
conveyed through a field. The tow bar assembly includes a primary
support beam having outer portions to which outrigger beams are
pivotally secured. Actuation devices are utilized between the
primary support beam and the outrigger beams to enable the
outrigger beams to be moved from a position wherein they are in
substantial alignment with the elongated axis of the primary
support beam to an orientation substantially perpendicularly with
respect thereto. A hitch dolly is connected by a universal swivel
joint to at least one and preferably each of the outrigger beams.
Each dolly includes at least one ground-engaging wheel and an
appropriate hitch to which an implement, such a hay baler, may be
selectively secured. In some embodiments, the dolly may also be
secured to the primary support beam so as to be intermediate the
dollies associated with the outrigger beams.
In the preferred embodiment, each dolly includes a pair of
spaced ground-engaging wheels for stabilizing the frame of the
dolly and an appropriate hitch for an agricultural implement to be
secured.
Although the tow bar assembly of the present invention is
specifically designed for use with heavier self-powered
agricultural implements, in some embodiments, one or more lighter
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weight implements may be towed and receive drive input power from
a hydraulic system associated with the tow bar assembly. In these
embodiments, hydraulic drive motors may be mounted on the
outrigger beams and/or primary support beam, however, when the
dollies are in use, the drive motors should be mounted to the
dollies.
Motors which are mounted to either the dollies or the primary
support beam or outrigger beams, when the dollies are not in use,
are hydraulically driven utilizing hydraulics which may include
fluid reservoirs mounted to the primary support beam and which are
connected to a pump for distributing hydraulic fluid to each of
the motors. In a preferred embodiment, the primary support beam
also functions as a hydraulic fluid reservoir and heat exchange
chamber for cooling hydraulic fluid during operation of any
agricultural implement being towed by the tow bar assembly.
The actuation devices are preferably hydraulic cylinders
which are secured to the outrigger beams and are directly
connected to the hydraulic system of the vehicle so as to be
controllable from the cab of the vehicle whereby the operator may
change the angular displacement of the outrigger beams relative to
the primary support beam as the implement is moved through a field
to thereby allow selective positioning of the agricultural
implements to adjust for spacing in windrows and to facilitate
maneuverability without requiring that the vehicle be stopped.
In the preferred embodiment, a third agricultural implement,
such as a hay baler, is towed utilizing a separate hitch is
provided along the central portion of the primary support beam to
which the tongue of the intermediately positioned implement is
pivotally secured. Such separate hitch may be associated with a
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central dolly. A drive input may also be provided for an
intermediate implement by mounting a hydraulic motor to the
primary support beam. This hydraulic motor may also be connected
to the hydraulic system and pump associated with the motors
associated with the outrigger beams.
In a further embodiment of the present invention, appropriate
electrical interface panels are provided along the primary support
beam for connecting the electrical controls on the self-powered
implements, such as a round hay balers, to controls extending from
the cab of the tractor. Appropriate control cables are provided
between the implements and the interface panels mounted to the tow
bar assembly and appropriate cables are extended from there to the
cab of the tractor such that the operator of the tractor may
manipulate the appropriate electrical controls associated with the
implements from the interior of the cab.
It is the primary object of the present invention to provide
a tow bar assembly which may be utilized to pull a plurality of
agricultural implements simultaneously through a field in such a
manner that the implements may follow the natural contour of the
ground by providing universal hitch joints to connect the
implements thereto.
It is yet another object of the present invention to enable a
plurality of agricultural implements, such as self-powered hay
balers, to be simultaneously pulled by a single tow bar assembly
in such a manner that the lateral spacing between the implements
may be changed while the implements are in motion and wherein
electrical controls to the implements are interfaced so as to be
accessible to the tractor operator from within the cab.
It is also an object of the present invention to provide a
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tow bar assembly for simultaneously towing a plurality of
implements wherein one or more of the implements may receive
driving power from a hydraulic system associated with the tow bar
assembly and wherein the hydraulic system includes at least one
pump which receives hydraulic fluid from a reservoir also
associated with the tow bar assembly.
According to a first aspect of the invention, a tow bar
assembly is disclosed for use in operatively connecting a
plurality of agricultural implements having hitch tongues to the
hitch of a tractor having a source of power supply. The tow bar
assembly comprises a primary support beam having opposite end
portions and a central portion and means are mounted to the
primary support beam for mounting the primary support beam to the
tractor hitch. The assembly also includes a pair of outrigger
beams and pivot means for pivotally mounting an inner end portion
of each of the outrigger beams to the opposite end portions of the
primary support beam. Means are provided for pivoting each of the
outrigger beams about the pivot means and each of the means for
pivoting includes a first end pivotally mounted to the primary
support beam and a second end pivotally mounted to one of the
outrigger beams. The assembly includes at least one dolly and
means for pivotally connecting the at least one dolly to one of
the outrigger beams. The at least one dolly includes a frame
supported by at least one ground engageable wheel and a hitch
member adapted to selectively pivotally connect the hitch tongue
of an agricultural implement thereto whereby an implement hitched
to the at least one dolly is pivotally connected to the tow bar
assembly so as to follow the contour of the ground over which the
implement is pulled.
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According to another aspect of the invention, a baling
implement for simultaneously baling forage material in a plurality
of rows is disclosed which is attachable to a tractor having a
power source. The baling implement comprises a plurality of
balers, each of which has a hitch tongue, and further includes a
primary support beam having opposite ends and a central portion.
Means are mounted to the central portion of the primary support
beam for mounting the primary support beam to the tractor hitch.
The implement also includes a pair of outrigger beams and pivot
means for pivotally mounting an inner end portion of each of the
outrigger beams to the opposite ends of the primary support beam.
Means are provided for pivoting each of the outrigger beams about
the pivot means and each of the means for pivoting includes a
first end pivotally mounted to the primary support beam and a
second end pivotally mounted to the outrigger beams. Means are
also provided for connecting at least one of the outrigger beams
to the hitch of one of the plurality of the balers and the means
for connecting includes at least one dolly having a frame
supported by a pair of spaced ground engageable wheels and a joint
connecting the dolly to the one of the outrigger beams to permit
pivotal movement about both a horizontal and a vertical axis with
respect thereto.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood with
reference to the attached drawings, wherein:
Fig. 1 is a top plan view of the tow bar assembly for
multiple agricultural implements of the present invention
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illustrating the manner in which the tow bar is utilized to
connect a plurality of hay balers to the hitch and hydraulic
controls of a conventional tractor and showing the implements
spaced at a maximum distance with respect to one another;
Fig. 2 is a top plan view of the tow bar assembly of Fig. 1
showing the outrigger beams and dollies associated therewith
realigned generally perpendicularly with respect to the primary
support beam and further illustrating the repositioning of the
implements relative to one another;
Fig. 3 is a partial front elevational view of the tow bar
assembly of Fig. 1;
Fig. 4 is a cross-sectional view taken along line 4-4 of
Fig. 1;
Fig. 5 is a cross-sectional view taken along line 5-5 of
Fig. 1;
Fig. 6 is a perspective illustrational view of the universal
pivot joint shown in Fig. 5;
Fig. 7 is a partial top plan view of the tow bar assembly of
Fig. 1 without motors; and
Fig. 8 is a view similar to Fig. 3 except not including any
drive motors associated with the dollies or primary support and
outrigger beams.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With continued reference to the drawing figures, the tow bar
assembly 10 of the present invention is illustrated in Fig. 1 as
being secured to the three point hitch "H" associated with a
conventional tractor "T". Power for manipulating the tow bar
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assembly, as well as for driving motors associated with some
embodiments thereof, is obtained by connecting hydraulic lines to
the hydraulic control circuit "C" associated with the tractor. A
more detailed discussion of the fluid circuit will be described in
greater detail hereinafter.
The present invention is designed to be utilized to
simultaneously tow a plurality of agricultural implements, such as
hay balers, by a single tractor. In this respect, the invention
will be described with respect to the use of three hay balers,
shown at HB1, HB2 and HB3 in the drawing figures. In some
instances, it may be desired to use only one or two hay balers HB1
and HB2 in combination with the tow bar assembly. In addition to
the foregoing, the present invention is also specifically designed
to be effectively utilized to tow either lightweight implements
which are generally not self-powered and which thus must receive
driving power from a power source associated with a tractor, or to
tow heavier implements, such as round hay balers, which include
their own power sources but which require electrical controls from
the cab of the tractor.
In Fig. 1, the hay balers HB1 and HB2 are shown as being
round hay balers of the type which include their own power sources
or motors "M" and thus do not require a separate input for
purposes of driving the hay balers during use but which include
electrical control circuits 15 which may be interconnected through
appropriate electrical cables 17 to an electrical interface panel
18 mounted to the primary support frame 20 of the tow bar
assembly. The electrical interface panel 18 is connected through
a primary control cable 22 to appropriate electrical controls
within the cab of the tractor. For purposes of example, the
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implement or hay baler HB3 is shown as being of the non-self-
powered type, thus requiring input from a drive shaft 23 which is
connected by way of a universal 24 to the drive mechanism (not
shown) of the hay baler.
As opposed to being a round hay baler, the baler HB3 may be a
square baler. Each of the balers includes a hitch tongue 25 which
is designed to be connected to the tow bar assembly as will be
described in greater detail hereinafter.
The primary support beam 20 is preferably formed of a
generally hollow metal material of rectangular cross-section and
includes a generally central portion and opposite end portions 26
and 27. The central portion of the primary support beam 20 is
further reinforced by an auxiliary beam 28 which is mounted in
generally parallel spaced relationship thereto and which is
connected to the central portion by means of a pair of spaced
outer plates 29 which are welded to both the auxiliary and primary
support beams.
Extending from the front wall of the primary support beam are
a pair of spaced mounting brackets 31 and 32 which are designed to
be engaged with the lower hitch links of the three point hitch "H"
of the tractor. The upper hitch link of the tractor is connected
to a pair of spaced brackets 33 mounted to the auxiliary support
beam 28. Utilizing the three point hitch of the tractor, portions
of the tow bar assembly may be raised for transport.
At each of the ends 26 and 27 of the primary support beam 20
are a pair of outwardly extending upper and lower plates 36 and 37
which are welded to the upper and lower walls of the support beam,
respectively. Outrigger beams 38 and 39, which are also formed of
a generally rectangular cross-sectional tubular steel or other
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metal material, are pivotally mounted by pivot pins 40 between the
upper and lower plates 36 and 37 so that the outrigger beams 38
and 39 may be pivoted relative to the primary support beam 20.
The outrigger beams 38 and 39 may be pivoted from a generally
aligned relationship with elongated axis "A-A" of the primary
beam, as shown in Fig. 1, to any selected angular relationship
generally rearwardly with respect to the primary support beam. In
Fig. 2, the outrigger beams 38 and 39 are shown as being oriented
generally perpendicularly with respect to the primary support
beam.
The tow bar assembly 10 includes a pair of ground-engaging
wheels 42 and 43 which are mounted to vertical struts 44 and 45
connected to brackets secured to the upper and lower plates 36 and
37 adjacent the opposite ends 26 and 27 of the primary support
beam. The angular positioning of each of the outrigger beams 38
and 39 is controlled by various actuation means which may be
incorporated with the tow bar assembly. In the preferred
embodiment, the actuation means are hydraulic cylinders 50 and 51
which are pivotally mounted at 52 and 53 to brackets 54 and 55
which are welded or otherwise secured to the primary support beam
adjacent the central portion thereof. The cylinders 50 and 51 are
oriented in a generally parallel relationship with respect to the
primary support beam when the outrigger beams 38 and 39 are
generally aligned parallel to the elongated axis "A-A" of the
primary support beam. Each hydraulic cylinder 50 and 51 includes
an extension rod 56 and 57 which is pivotally mounted at 58 and
59, respectively, to brackets 60 and 61 which may be fixedly
secured or adjustably mounted along the length of the outrigger
beams 38 and 39. When the hydraulic cylinders are activated so as
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to urge the extension rods 56 and 57 to a fully retracted
position, as shown in Fig. 2, the outrigger beams 38 and 39 are
moved to a position wherein they are oriented generally
perpendicularly rearwardly of the primary support beam.
The present invention is specifically designed to enable a
single tow bar assembly to manipulate a plurality of self-powered,
and therefore larger and heavier, farm implements and especially
hay balers, such as shown at HB1 and HB2. In keeping with the
teachings of the invention, a11 three of the implements to be
towed by the tow bar assembly may be self-powered implements or,
in the alternative, a11 three or any one or two implements may be
of the lighter weight type requiring an exterior drive input, such
as shown at 23 in Fig. 1.
To enable larger equipment to be stabilized when being pulled
by the tow bar assembly in the preferred embodiment, the present
invention incorporates a plurality of dollies 64, 65 and 66, each
of which is supported by at least one ground-engaging wheel. As
shown in the drawing figures, it is preferred that each dolly
includes a frame including a cross-beam 67 from which extends
spaced vertical struts 68 and 69, each of which is connected by a
stub shaft or axle at the lower end thereof to a pair of spaced
wheels 70 and 71, respectively. Reinforcing flanges 72 and 73 are
provided between the cross beam and each of the struts 68 and 69.
With specific reference to Figs. 5 and 6, each of the dollies
further includes a pair of rearwardly extending hitch plates 74
and 75 having aligned openings therein for receiving a hitch pin
76 by way of which the dollies are connected to the hitch tongue
25 of an implement in such a manner that the hitch tongue of the
implement is pivotable in a horizontal plane about the pin 76.
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Due to the weight of the implements and the amount of load which
is placed on the hitch tongue 25 when the tow bar assembly is in
use, it is necessary that the dollies follow the natural contour
of the surface over which the implements are being used. In this
respect, each dolly includes a universal pivot joint or swivel 78
by way of which the dolly is secured to either one of the
outrigger beams 38 or 39 or to the primary support beam 20 of the
tow bar assembly.
As shown in the drawing figures, the dolly 64 is connected to
the outer end portion of the outrigger beam 38 and dolly 66 is
mounted to the outer end portion of outrigger beam 39 while dolly
65 is mounted generally centrally of the primary support beam 20.
To provide necessary pivotal movement between each dolly and a
respective outrigger beam or primary support beam, each of the
universal joints includes a pin 79 which extends through the cross
beam 67 thereof to which the base 80 of the generally U-shaped
swivel hitch joint 78 is rotatably mounted. The pivot includes
parallel plates 81 and 82. The end of the pin 79 is bolted or
otherwise secured in such a manner that the base 80 of the hitch
joint is rotatable about the horizontal axis defined by the pin
79. Each of the plates 81 and 82 has an aligned opening therein,
as shown at 83 and 84, for purposes of receiving a hitchpin 85
which is mounted through an opening in the associated outrigger
beam 38 or 39 or the primary support beam 20. The universal
swivel hitch 78 permits the dolly to both pivot about a horizontal
axis relative to either the outrigger beams or the primary support
beam and to further pivot about a vertical axis relative thereto
so that the dolly wheels may track the terrain over which an
implement is being pulled and thereby reduce the tongue weight on
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the tow bar assembly. With specific reference to Fig. 3, the
dolly 64 is shown as being pivoted about the horizontal pin 79 in
order to allow the wheels 70 and 71 to follow the contour of the
ground.
With specific reference to Fig. 7, it should be noted that
when the hydraulic cylinders 50 and 51 are activated to retract
the cylinder rods 56 and 57 in order to move the outrigger arms 38
and 39 to a more perpendicular relationship with respect to the
main support beam 20, the mounting brackets 60 and 61 are spaced a
sufficient distance relative to the dollies 64 and 66 so as to not
interfere with the movement of the dollies to a trailing position
as shown in Fig. 2 of the drawing figures.
As previously discussed, the present invention may be
utilized either with self-powered or non-powered implements.
Figs. 7 and 8 show the tow bar assembly without any type of motors
for powering an agricultural implement, whereas Figs. 1 and 2
disclose the mounting of motors for purposes of driving
implements. In these embodiments, brackets 86 are mounted to the
upper control portion of each of the cross-beams 67 of the
dollies. Hydraulic motors 88, 89, 90 are mounted to the brackets
86 with each including a drive shaft 91, 92 and 93, respectively,
which are connected to universal couplers 94, 95 and 96 which
engage the outer end portions of input drive shafts, such as shown
at 23 in Fig. 1. Due to the universal couplers, it is possible to
drive the input shafts 23 regardless of the orientation of the
hydraulic motor pumps 88, 89 and 90 relative to the hay balers,
such as shown at HB3. It should be noted that the angular
orientation of the input shafts 23 varies dependent upon the
angular relationship of the dollies relative to the implement.
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To supply fluid power to the hydraulic motors 88-90, the tow
bar assembly 10 is designed to provide a source of hydraulic
fluid. In this respect, mounted adjacent each of the opposite
ends of the primary support beam are a pair of hydraulic fluid
tanks 100 and 102 which are designed to hold sufficient hydraulic
fluid for the operation of the various motors. Tank 100 includes
a fluid inlet 103 from which hydraulic fluid is received from a
filter 104 by way of a flow line 105. The filter 104 is connected
by a hydraulic lines 106 and 106' extending from the outlet of
hydraulic motors 88 and 89. Hydraulic tank 102 includes a fluid
inlet 107 which is connected to a filter 108 by way of a fluid
line 109. The filter 108 is connected to a hydraulic line 110 to
the outlet of the motor 90. Both of the hydraulic tanks 100 and
102 have discharge outlets (not shown) which communicate the tanks
with an interior chamber (not shown) defined within the primary
support beam 20. The interior chamber thereby acts as a heat
exchange reservoir for cooling the hydraulic fluid during the use
of the tow bar assembly.
To supply hydraulic fluid to the motors 88-90, a hydraulic
pump 112 is mounted between the primary support beam and the
auxiliary beam, such as shown in Figs. 3, 4 and 7. Hydraulic
lines are provided for connecting the pump to the chamber within
the primary support beam 20. The fluid is discharged through the
motor by way of hydraulic lines 113, 114 and 115 to the motors.
To control the hydraulic pumps, valves 116 and 117 are placed
within the fluid circuit adjacent to the filters 104 and 108 for
regulating the rate of fluid flow through the circuit.
Hydraulic fluid for operating the hydraulic cylinders 50 and
51 is provided directly from the hydraulic control circuits "C"
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associated with the tractor. In this respect, hydraulic cylinder
50 is connected by hydraulic lines 120 and 121 to the control
circuit "C" and hydraulic cylinder 51 is connected to hydraulic
lines 122 and 123. As these lines are directly connected to the
tractor's control circuit, the tractor operator may control the
extension and retraction of the rods associated with the cylinders
from the cab of the tractor. Power for the hydraulic pump 112 is
obtained using a drive connection 130 from the power takeoff of
the tractor.
In use of the tow bar assembly of the present invention, one
or more farm implements, particularly hay balers, either self-
powered or non-powered, may be secured to the tow bar assembly.
Generally, after hay or other forage material has been cut and
harvested, it is raked into windrows which may vary in spacing,
depending upon field conditions and other parameters. The present
invention allows up to three windrows to be baled simultaneously.
The general overall width of the unit when the outrigger beams are
expanded, such as shown in Fig. 1, is approximately 16 feet with
the outside dollies adding an additional three to four feet to
each end. By the operator manipulating the hydraulic cylinders 50
and 51, the spacing between the outer hay balers or implements and
the central implement may be adjusted. The universal joints
associated with each of the dollies allows the implements to
follow the contour of the land.
Although not specifically noted, in one embodiment of the
invention, the intermediate dolly may be dispensed with and a
conventional or universal hitch, as previously discussed, may be
supplied directly to the primary support beam 20. In this
embodiment, either one or both of the outer dollies would be
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utilized with the tow bar assembly. Also, motor 89 could be
mounted directly to the primary support beam. In a like manner,
if the dollies 64 and 66 are not in use, the motors 88 and 90
could be mounted to the outrigger beams.
The foregoing description of the preferred embodiment of the
invention has been presented to illustrate the principles of the
invention and not to limit the invention to the particular
embodiment illustrated. It is intended that the scope of the
invention be defined by a11 of the embodiments encompassed within
the following claims and their equivalents.
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