Apparatus for driving transverse shafts of a baler

A drive system for a baler of large cylindrical bales that permits a plurality of transverse driven shafts to be slidably engaged and disengaged for quick and easy assembly and repair of the baler. The transverse driven shafts extend between a pair of spaced apart sidewalls. A gear box for each of the driven shafts is mounted on one of the sidewalls and includes longitudinal drive surfaces. Mating longitudinal drive surfaces are formed on the driven shafts for slidable engagement with and disengagements from the drive surfaces of the associated gear box. A releasable mounting secures the nondriven ends of the shafts at the opposite sidewall.

BACKGROUND OF THE INVENTION 
The invention relates to drive systems for agricultural equipment and, more 
specifically, to a drive system for a baler of large cylindrical bales 
consisting of gear boxes and a plurality of transverse shafts and rollers 
driven by the gear boxes and slidably disengageable therefrom for easy 
assembly and repair of the baler. 
In recent years, the agricultural practice of collecting crop materials, 
such as corn stalks, straw, green forage crops, and grasses, has been 
revolutionized by baling machines which produce large cylindrical bales of 
up to approximately six feet in diameter. Examples of such baling machines 
are described in U.S. Pat. Nos. 3,722,197 and 4,172,354. Such machines 
include two, opposite and spaced apart side walls that support a plurality 
of transverse shafts or rollers extended therebetween. A plurality of 
endless belts are trained about the shafts and define a baling chamber in 
which the large round bale is formed. A crop pick-up mechanism picks up 
crop material off the ground and feeds it into the baling chamber where 
the plurality of endless belts roll and compress the crop material into a 
large cylindrical bale. 
Most such baling mechanisms are driven from the power take-off of a tractor 
which is used to pull the baling machine over the ground. A main drive 
sprocket located on the outside of one of the side walls is interconnected 
to the tractor power take-off typically by a 90-degree gear box. A 
plurality of roller chains are used to transmit rotation of the main drive 
sprocket to certain of the transverse shafts for driving the shafts and 
thereby the plurality of endless belts. A roller chain also is used to 
transmit rotation of the main drive sprocket to a drive mechanism for the 
crop pick up means. 
The roller chains and sprocket drive mechanism suffers from a number of 
draw backs and limitations. The chains must be constantly lubricated by a 
brush and drip system or the like. Although the chains are typically 
housed behind a shield, the baling operation gives rise to large amounts 
of chaff and other finely divided crop material that finds its way inside 
the housing and collects on the oiled chains and sprockets. Roller chains 
also stretch as a result of use and so to maintain the required tension 
requires either the use of a spring-loaded idler or the like or periodic 
adjustment. Further, the endless chains carry a substantial load during 
operation and can, if improperly maintained, break and cause bodily injury 
to an operator. 
The roller chain and sprocket drive mechanisms also are difficult to 
assemble and disassemble with the result that the balers are fully 
assembled at the manufacturing site and shipped in the assembled 
condition. The balers enclose a large volume of empty space in the 
assembled condition and, accordingly, take up a lot of costly shipping 
room. Repairs that require disassembly of the driven transverse shafts 
from the associated sprockets and mountings are slow and difficult. A 
common repair on the balers is the replacement of a failed belt. 
Continuous, seamless belts have been developed which may reduce belt 
failures. The time and difficulty of removing the driven transverse shafts 
and rollers that would be necessary to use such belts is one reason that 
has prevented their adoption and use. 
SUMMARY OF THE INVENTION 
An object of the present invention is to provide a drive system for 
transverse shafts and rollers of a baler which does not use sprockets 
attached to the driven shafts or rollers. 
Another object of the present invention is to provide a drive system for a 
baler wherein a gear box is associated with a driven end of each 
transverse driven shaft or roller of the baler. 
A further object of the invention is to provide a drive system for a baler 
wherein longitudinal drive surfaces of the gear boxes are slidably engaged 
with mating longitudinal drive surfaces on each of the transverse driven 
shafts or rollers. 
Still a further object of the invention is to provide a drive system for a 
baler which permits the easy disassembly of the driven transverse shafts 
from the gear boxes to facilitate repairs of the drive system. 
Yet another object of the invention is to provide an improved drive system 
for a baler which will permit the assembly of the baler from components by 
nonfactory personnel so that the balers can be transported in a 
knocked-down condition thereby greatly reducing the shipping volume of the 
baler and, accordingly, the cost of shipment. 
Other objects and advantages of the invention will be apparent from the 
following description of the invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
There is illustrated in FIG. 1 generally at 10 a tractor drawn, ground 
supported baler for forming large round bales of crop material. A draw 
tongue 12 extends forwardly of the baler 10 for attachment to a tractor 
(not shown) or similar motive means. As best illustrated in FIG. 2, the 
baler has a pair of opposite side walls, right side wall 14 and left side 
wall 16. Extended between the side walls 14 and 16 are a plurality of 
transverse shafts or rollers including idler belt rollers indicated 
generally at 18 with individual idler belt rollers separately identified 
as 18a-h, driven belt rollers indicated generally at 20 with individual 
driven belt rollers separately identified as 20a and 20b, drum 22, and a 
starter roller 24 (FIG. 6). The rollers 18 and 20 and drum 22 have stub 
shaft end portions while the starter roller 24 has a through shaft. A 
plurality of endless belts 26 are trained about the idler belt rollers 18 
and driven belt rollers 20. A belt tension arm 28 is pivotally attached at 
30 to both side walls 14 and 16. The free end portion of the belt tension 
arm 28 carries a pair of idler rollers 32 and 34 about which the plurality 
of belts 26 are also trained. As is well known, the belt tension arm 28 
maintains the appropriate tension in the plurality of belts 26 during 
formation of a bale. The belt tension arm 28 and endless belts 26 are 
shown in FIG. 1 in the position wherein a fully formed bale is inside the 
baler 10. 
In the formation of a bale, the belts 26 are moved in a direction so that 
the nearly vertical runs at the front of the baler 10 travel in the upward 
direction. Motion of the belts 26 is caused by frictional engagement 
thereof with the driven transverse rollers 20a and 20b. The baler is 
operated from the power take-off of a tractor through a direct drive train 
illustrated diagrammatically in FIG. 6. The tractor power take-off is 
connected to an input shaft 36 of a right-angle gear unit 38 of the 
conventional type. An output shaft 40 of the right-angle gear unit 38 
extends transversely outside of the side wall 14 to a main gear box unit 
42. A first output or drive shaft 44 extends vertically from the main gear 
box unit 42 to a first driven roller gear box unit 46. A second output or 
drive shaft 48 extends from the main gear box unit 42 rearwardly to a 
starter roller gear box 50. A second driven roller gear box 52 is driven 
by a short output or drive shaft 54 (FIG. 1) of the first driven roller 
gear box unit 46. A drum roller gear box unit 56 is driven by an output or 
drive shaft 58 of the starter roller gear box unit 50. Each of the gear 
boxes 42, 46, 50, 52 and 56 are mounted on the side wall 14. Energy for 
rotating the transverse shafts and rollers 20a, 20b, 22, and 24, is 
transmitted from the power take-off of the tractor through the direct 
drive train. 
Each of the gear box units 42, 46, 50, 52, and 56, are very similar in 
construction. A representative gear box is illustrated in FIG. 3. The gear 
box unit includes an outer housing 60 which is mounted on a mounting 
flange 62 that is secured to the side wall 14 of the baler. The, housing 
60 encloses a bevel gear system and a planetary gear system. In the gear 
box illustrated in FIG. 3, the end portion of a first shaft 64 (which may 
be any of the shafts 44, 48, 54 or 58) is rotatably mounted to the housing 
60 by a pair of bearings 66 and 68. A bevel gear 70 is carried on the 
shaft 64. A second shaft 72 (which may be any of the corresponding ones of 
the shafts 44, 48, 54 or 58) also has an end portion rotatably mounted to 
the housing 60 and carries a bevel gear 74. Each of the bevel gears 70 and 
74 are also in drivable meshing engagement with an axial bevel gear 76 
which is mounted inside the housing 60 by a bearing 78 for rotation about 
an axis substantially perpendicular to the side wall 14. Thus, rotation of 
either first shaft 64 or second shaft 72 will result in corresponding 
rotation of the other shaft and of the bevel gears 70, 74 and 76. 
The planetary gear system inside the housing 60 includes a planetary gear 
carrier 80 (FIG. 3 and 4). A bearing 82 supports the planetary gear 
carrier 80 for rotation inside the housing 60 in coaxial alignment with 
the axial bevel gear 76. The planetary gear carrier 80 carries three 
planetary gears 84 equally spaced about the central axis thereof, each 
planetary gear 84 being supported for rotation inside a recess 86 about a 
shaft 88. The planetary gears 84 are in driving engagement with an 
internal ring gear 90 on an internal circumference of the housing 60. The 
planetary gears 84 are also in driving engagement with a sun gear at the 
end portion of a shaft 92 of the axial bevel gear 76. Accordingly, the 
rotation of the bevel gear 76 will simultaneously rotate each of the 
planetary gears 84 about their respective shafts 88 of the planetary gear 
carrier 80. Rotation of the planetary gears 84 causes them to revolve 
inside the housing 60 in engagement with the ring gear 90. 
A representative driven roller 94 (which may be any of the rollers or 
shafts 20a, 20b, 22 and 24) is illustrated in FIG. 3. An end portion of 
the driven roller 94 extends into the planetary gear carrier 80. Driven 
roller 94 and the planetary gear carrier 80 are in driving engagement by 
way of a flexible spline formed by intermeshing teeth 96 of the planetary 
ring carrier 80 and teeth 98 of the driven roller 94. A press-fit oil plug 
99 prevents the lubricating oil inside the gear box from leaking out 
around the roller 94. 
In the preferred embodiment, a shaft support toroidal ring 100 is seated 
inside a recess therefor in the planetary gear carrier 80 adjacent to the 
teeth 98. The shaft support ring 100 provides a bearing surface for a 
reduced diameter shoulder portion 102 of the driven end portion of the 
driven roller 94. 
In a second embodiment of the shaft support ring, illustrated in FIG. 7b, a 
larger bearing surface is provided by a wide split ring 104 that includes 
an inner retaining ring 106. The shaft support toroidal ring 100 permits 
more flexibility of the flexible spline but presents a smaller bearing 
surface. The wide split ring 104 has a larger bearing surface but somewhat 
reduced flexibility. The selection of which of the two preferred 
embodiments should be used will depend on the design and application of 
the driven roller 94. 
The nondriven end of the driven roller 94 is illustrated in FIGS. 5 and 
10-12. A pair of mounting flanges 108a and 108b are attached to the side 
wall 16. A nondriven end portion 95 of the driven roller 94 is received 
for rotation inside a spherical bearing 110 that is attached by way of a 
two-part flangette 112 to a bearing mounting bracket 114 by four bolts 
93a-d. The bearing 110 rests against a spacer 97 and is held in place by a 
bearing locking collar 99. A cap 101 and hex bolt 103 combination threaded 
in the end of the roller 94 secure the locking collar 99. A pair of 
mounting bolt and nut combinations 116a and 116b pass through and support 
the bearing mounting bracket 114 on the mounting flange 108. Oversized 
bolt openings 118 of the mounting flange 108 permit limited adjustment of 
the position of the spherical bearing 110. 
The spherical bearing 110 and its adjustable and somewhat flexible mounting 
structure will accommodate the range of axial variation in the position of 
the nondriven end of the driven roller 94 that commonly results between 
ideal design and actual manufactured machines. The flexible spline 
connection at the driven end of the roller 94 also accommodates the 
typical variations in axial alignment of the roller 94 and its mounted 
ends. 
In the preferred embodiment, all five of the driven transverse shafts or 
rollers are driven by a corresponding gearbox. The nondriven end of the 
starter roller 24 supports a roller chain sprocket that is drivably 
engaged via a roller chain with a crop pick-up of the baler. In an 
alternative embodiment, as illustrated in FIG. 8, the drum roller gearbox 
unit 56 is omitted. The drum roller 22 is instead driven off of the 
nondriven end of the starter roller 24 by a triangular chain drive, 
indicated generally at 122, including a roller chain that is trained about 
sprockets on the ends of the crop pick up, drum roller, and starter roller 
on the side of the baler opposite of the gearbox units. 
The prior art balers use a roller chain drive system for all of the driven 
shafts and rollers (FIG. 9). The power input shaft 40 extends to the side 
16 of the baler 10 from the right angle gearbox as in the preferred 
embodiment. Rather than gearboxes and interconnecting drive shafts, 
however, the driven ends of the rollers and shafts have one or more chain 
sprockets attached to them and five roller chains 124a-e drivably 
interconnect the driven rollers and shafts to the input shaft 40. 
The belts used in balers heretofore have been endless loops created by 
joining the two ends of a strip of belting by metal "stitches". This 
juncture is a frequent failure site of the belts. At least one 
manufacturer is developing nonstitched endless belt loops that are 
expected to be more durable. With prior art balers the endless belts would 
most typically be used as original equipment, put in place when the baler 
is assembled. As illustrated in FIG. 1, replacing a belt with a continuous 
loop would require removal of each of the idler belt rollers 18a-h and the 
driven belt rollers 20a and 20b, but none of the other transvetsely 
extended members. If a belt breaks after assembly, it is too inconvenient 
to remove an end of each of the belt rollers in order to replace a belt 
loop. With the present invention, the driven belt rollers 20a-b are easily 
removed by withdrawal of the bolt 116a at the nondriven end. The entire 
roller may then be removed by pulling along the longitudinal axis. The 
driven end of the roller will slide out of the spline of the planetary 
gear carrier. This feature is present on the other driven shafts and 
rollers as well, being inherent in the design of the gearboxes. This 
greatly simplifies assembly of the baler by permitting the transverse 
driven shafts and rollers to be assembled merely by axially aligning and 
then sliding the driven end into the spline of the corresponding gearbox. 
In contrast with the prior art, accordingly, the ease of assembly will 
permit the balers to be shipped in a "knocked-down" condition for later 
assembly by a relatively unsophisticated dealer or customer, thus offering 
the possibility of substantial savings on shipping costs. Other transverse 
members of the baler extending between the sidewalls must, of course, also 
be removed to permit the sidewalls to be collapsed. The drive system of 
the present invention simplifies the assembly and disassembly of the 
driven belt rollers 20, the drum 22 and the starter roller 24 without 
adversely affecting the ease or difficulty of assembling or removing the 
other transverse members. 
In the preferred embodiment, the following drive shaft speeds and gear 
ratios are used (assuming tractor PTO speed of 540 rpm). 
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Gear box Planetary Side 
Bevel Side 
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Right angle 38 N/A 1:1 
Main gearbox 42 1:2.8 1:1.2 
First driven roller 
4.0 1.35:1 
gearbox 46 
Second driven roller 
4.0 1.35:1 
gearbox 52 
Starter roller 4.0 1:1 
gearbox 50 
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Shaft RPM 
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Input shaft 36 540 
Output shaft 40 540 
First drive shaft 44 1814 
Second drive shaft 48 1814 
Driven belt roller 20b 334.2 
Short drive shaft 54 1814 
Driven belt roller 20a 334.2 
Starter roller 24 453.6 
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The main gearbox 42 functions as the primary speed increase mechanism for 
the drive system. In an alternative embodiment, a planetary gear unit is 
added ahead of the right angle gearbox 38. This would permit lighter drive 
shafts to be used to transmit the same work at the higher rotational 
speeds. 
Specific details on the flexible external involute spline that connects the 
ring gear carrier 80 and the drive end of the shaft or roller 94 are: (a) 
number of teeth=20; (b) pitch=12/24; and (c) pressure angle=30.degree.. 
Although the invention has been described with respect to a preferred 
embodiment thereof, it is to be understood that it is not to be so limited 
since changes and modifications can be made therein which are within the 
full intended scope of this inven-tion as described in the following 
claims.