Round baler and discharge means

A tractor drawn and powered machine is disclosed for forming large round bales of fibrous agricultural crops in a chamber of fixed size. The baling chamber consists of a lower and an upper section. The lower section includes a wheel mounted main frame, along with a pickup reel and a bottom conveyor comprising side by side belts entrained on four transversely extending rollers. The upper section is supported on a subframe which is hinge mounted along its front edge to the main frame allowing thereby the rear portion of the upper section to open as a rearward facing tailgate for discharge of a completed bale. Situated within the subframe of the upper section are all of the conveying elements which make up the rear, top and front of the generally cylindrical periphery of the baling zone. Each conveyor element in the upper section comprises a plurality of side by side belts entrained on spaced apart transversely mounted upstream and downstream rollers. A space between the last of the serially arranged conveying elements and the uppermost surface of the bottom conveyor provides an inlet into the baling chamber. During the bale forming operation a latch mechanism holds the tailgate closed. When a bale is ready for discharge the tractor is halted, the tailgate is opened by a hydraulic cylinder and the bale is conveyed out the rear of the machine. As soon as the bale falls to the ground, the tailgate can be reclosed making the machine ready for pickup of more crop material with which to form another bale.

BACKGROUND OF THE INVENTION 
This invention relates to a machine for forming large round bales of 
fibrous agricultural crops. Our machine improves on the existing art in 
that the gate, through which a completed bale is discharged, can be 
reclosed without having to move the baler forward to obtain clearance. 
Many bale forming machines exist which form fibrous agricultural crops into 
bales that are either twine or wire tied. For example, the U.S. Pat. No. 
4,009,653 to Sacht discloses a method for forming large round bales in a 
machine comprising a cage-like frame having a horizontal axis and a 
generally cylindrical shaped baling zone. Upwardly extending machine 
sidewalls form the confining end surfaces of the baling zone. A plurality 
of serially arranged conveying elements enclose and generally define the 
circumferential periphery of the baling zone. Thus, the size of the baling 
chamber remains constant during the bale forming process. To accomplish 
discharge of a completed bale, the baling chamber is divided into two 
portions approximately along a vertically extending axis cutting plane. 
The rear portion of the housing is then configured to swing upward from a 
hinge point at the top, thereby allowing the bale to be discharged 
rearward. 
The U.S. patent application having Ser. No. 162,372 and now U.S. Pat. No. 
4,319,446 and assigned to the same assignee as this application discloses 
bale forming means which differ somewhat from the implementation of Sacht. 
Two additional rollers are added to support the bottom conveyor belts. As 
viewed from the side the improved system shows four rollers on which a 
plurality of laterally spaced belts are trained. The second and third 
rollers (which are respectively in the forward and aft portions of the 
conveyor midsection) and the fourth roller (which is at the rear of the 
machine) are disposed to be generally on the cylindrical periphery of the 
baling zone. The first roller is in front of and somewhat below the plane 
containing the axis of the third roller. The Arnold et al. invention 
improves on Sacht in two ways. First, the vertical dimension of the 
entrance throat is enlarged. This allows the baler to operate in a heavier 
stand of hay without becoming clogged. Second, by lowering the placement 
of the front roller, a pickup reel of smaller diameter can be used. This 
permits the flow of hay being picked up from the windrow to pass into the 
baling zone without undergoing abrupt changes in direction. The laterally 
spaced conveyor belts accept the crop material being passed on from the 
pickup reel and frictionally engage the crop strands to provide inward 
directed pressure to carry them into the baling zone. 
This invention is shown in conjunction with a baler having a bottom 
conveyor member for receiving agricultural material which is constructed 
similar to that disclosed in the U.S. patent application having Ser. No. 
162,372. Using this type of bottom conveyor, generally cylindrical bales 
are formed in a cavity of fixed size. The partially completed bale rotates 
on a horizontal axis while crop material picked up from a windrow is 
continuously added to the periphery of the bale. As the baling chamber 
fills, pressure is exerted on the surrounding enclosure. The enclosure is 
hinged along the front edge to allow the upper portion to open from the 
rear like a clam shell to enable discharge of a completed bale. A latch 
mechanism holds the opposing faces of the enclosure together until the 
bale is complete. 
With our invention discharge of the completed bale is accomplished in a way 
which improves on Sacht. With the Sacht teaching, the rear portion of the 
baler housing swings upward from a hinge point at the top. Discharge of 
the bale leaves it under the overhanging raised portion of the tailgate 
structure. Before the tailgate can be closed, the operator has to move the 
baler ahead some eight or ten feet to allow the raised structure to clear 
the bale which is lying on its side on the ground. Since the baler has to 
be moved ahead to allow the tailgate to be closed, the operator of the 
Sacht machine goes through a sequence as follows. He stops his forward 
process along the windrow when a bale is formed. He then shifts the 
tractor into reverse, backing the baler up ten feet or thereabouts. The 
bale is then discharged and the tractor placed in forward drive. After 
driving ahead a few feet to enable the raised structure to clear the bale, 
the tractor clutch is then depressed and the tailgate of the baler closed. 
With the tailgate closed, the baler is ready to resume forward progress 
along the windrow. 
Using our improved baler, the operator does not have to backup his machine 
to discharge a bale. The discharged bale does not prevent immediate 
closure of the tailgate since it is not deposited on the ground in an area 
which is under the overhanging raised structure. This ability to 
immediately close the tailgate saves time as well as wear and tear on both 
the tractor and the operator. 
SUMMARY OF THE INVENTION 
It is an object of this invention to provide a machine for forming large 
round bales of fibrous agricultural crops which is simple to operate. The 
baler that was first reduced to practice forms generally cylindrical bales 
in a chamber of fixed size. During the bale forming process, the partially 
completed bale rotates on a horizontal axis while crop material picked up 
from a windrow is continuously added to the periphery of the bale. As the 
baling chamber fills pressure is exerted on the peripheral elements of the 
enclosure. The enclosure is hinged along the front edge to allow the upper 
section to open like a clam shell for rearward discharge of a completed 
bale. A latch mechanism holds the opposing faces of the enclosure together 
until the bale is complete. 
A key element in the implementation of our invention is the placement of 
the hinge point of the moveable upper section. We placed it at the most 
forward edge of the baling chamber, putting it generally at the same 
height above ground as the central axis of the chamber. 
The upper section comprises a subframe covered by protective panels 
including a pair of spaced apart sidewalls mounted at right angles to the 
central axis of the baling chamber. Also situated in the moveable upper 
section are all of the conveying elements with the exception of the bottom 
conveyor. This includes those conveying elements which are serially 
disposed around the rear, top and front of the generally cylindrical 
periphery of the baling zone. This means that only the bottom conveyor is 
not enclosed in that portion of the baler which swings upward like a clam 
shell to provide a tailgate through which a completed bale can be 
discharged. Each conveyor element in the upper section comprises a 
plurality of side-by-side belts which are entrained on first and second 
spaced apart rollers having horizontal axes, the ends of each roller being 
journalled in the sidewalls of the moveable upper section. The rollers at 
the downstream end of each conveying element are synchronously driven from 
the PTO of the tractor. There is a space between the last of the serially 
arranged conveying elements and the uppermost surface of the bottom 
conveyor. This space provides an inlet to the baling chamber which extends 
the full width of the baler. The outwardly extending axial shaft of the 
last downstream roller additionally serves as the hinge point around which 
the upper section pivots. A hydraulically actuated piston appropriately 
mounted between the upper section subframe and a location on the main 
frame just forward of the hinge point serves as a motive force to open and 
close the tailgate. 
As the bale forming sequence commences, crop material from the windrow will 
be picked and delivered into the baling chamber. As more and more material 
is gathered in, the conveying element belts roll the strands into a bale 
which fills the chamber from sidewall to sidewall. As the chamber fills, 
compressive forces exerted on the bale cause the tailgate to try to open. 
This places a load on the latch mechanism which holds the gate in the 
closed position. By placing a sensor in cooperation with the latch, it is 
possible to measure when a bale is ready for discharge. When the sensor 
reaches the tripped position, the operator will be alerted to the fact 
that a bale is completed. 
At this time the operator stops the tractor to halt flow of crop material 
into the baling chamber. The bale is tied off with twine and the bale 
ejection sequence initiated. Bale ejection is accomplished by actuating 
the hydraulic piston which rotates the upper section around the hinge 
point. The tailgate opens sufficiently wide to enable the bale to pass 
rearwardly therethrough. The bottom conveyor moves continuously in a front 
to back direction throughout the discharge sequence causing the completed 
bale to drop off the back of the baler. A cross frame member positioned 
just rearward of the bottom conveyor assures that the bale drops onto the 
ground in a position which clears rotating machine components of the 
conveyor. 
Once the bale has been discharged, the tailgate can be closed immediately. 
There is no need to move the baler forward in order to have the tailgate 
section clear the discharged bale. This means that our baler does not have 
to be backed up for bale discharging. The operator needs only to stop his 
tractor when he receives a signal that the baling chamber is full. The 
operator runs the PTO continuously during the entire baling cycle. When 
the forward motion of the baler is stopped and the bale is tied off it can 
then be discharged. When that sequence is complete and the tailgate 
reclosed, the operator engages the tractor in drive and proceeds along the 
windrow to form another bale.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 shows a rear view of a baler 10 which is capable of gathering crop 
material from a windrow and forming it into round bales generally 
cylindrical in shape. Baler 10 is supported by a pair of wheels 12. The 
baler is intended to be drawn behind a tractor and to be powered therefrom 
by means of a power-take off. The manner in which the baler operates is 
better seen by reference of FIG. 2. Baler 10 having wheels 12 supported 
from frame 15 is drawn behind a tractor by hitch 14. When appropriately 
drawn behind a tractor, astride a windrow of crop material 16, the baler 
gathers up the crop by means of pickup reel 18. 
Pickup reel 18 delivers the crop material to a conveyor which forms the 
bottom of the baling zone. The conveyor comprises a plurality of 
side-by-side belts 20 which are carried over transversely extending 
rollers 22, 24, 26 and 28. In the unit reduced to practice 5 belts 20 were 
used to span a baling chamber 5 feet long. Rollers 24, 26 and 28 are 
generally on the periphery of the cylindrical shaped baling zone. Roller 
22 is mounted lower than roller 24. This is done so that a line drawn 
tangent from the top of pickup reel 18 to the top of roller 24 passes 
tangentially over roller 22. This and a plurality of side-by-side guidance 
tines 17 help in the delivery of crop material to the baling zone. 
Above the bottom conveyor is a series of independent conveyor assemblies 
which generally surround the cylindrical baling zone. Three such conveyor 
asemblies are shown. As implemented, they are of identical configuration. 
The rearmost of the serially arranged conveyor assemblies consists of 
upstream roller 29, downstream roller 31 and a multiplicity of 
side-by-side conveyor belts 30. Similarly, the topside conveyor assembly 
consists of downstream roller 35, upstream roller 33 and conveyor belts 
32. The front conveyor assembly is made up of belts 34, downstream roller 
36 and upstream roller 37. Rollers 29, 31, 33, 35 and 37 are journalled 
for rotation in the sidewalls of subframe 40. Subframe 40 is hinged at the 
front by the bearings (not shown) which secure the extended shaft of 
roller 36 to mainframe 15. Pivoting subframe 40 about roller 36 allows the 
rear edge 44 (See FIG. 3) to swing upward to provide a tailgate through 
which a completed bale can be discharged. 
A latching mechanism to maintain the tailgate in a closed position is shown 
in FIG. 1. As shown in FIG. 1, the latch assembly comprises a transversely 
extending torque tube 46 rotatably mounted in bearing plates 48 and 49. On 
the left end of torque tube 46 is a first member in the form of latch 
plate 50. On the right end is a second like latch plate 52. There is a 
spring 54 having one end attached to latch plate 50 and its second end 
anchored to a bracket 55 that is secured to subframe 40. Spring 54 holds 
latch plate 50 against a pin 56 which is anchored to the baler frame. A 
slot formed in latch plate 50 allows the latch plate to lock the tailgate 
in the closed position. Latch plate 52 also has a similar slot which 
operates in conjunction with another pin extending from the far side of 
the baler frame. There is also a second spring 54 on the right side of the 
baler. 
A crankarm 58 extends rearward from torque tube 46. A clevis arrangement 
secures one end of cable 60 to the outer end of crankarm 58. The second 
end of cable 60 is secured by means of a second clevis to pivot arm 62. 
Idler pulley 64 allows cable 60 to change directions and make connection 
with the end of pivot arm 62. An upward pull on cable 60 rotates the 
torque tube so that latch plates 50 and 52 are released from left side pin 
56 and the pin to which latch 52 attaches. Release of the pull on cable 60 
allows springs 54 to relatch the plates 50 and 52 to pins 56. 
As the bale is formed it rotates in a clockwise direction as viewed in FIG. 
2. Rotation is brought about by contact with belts 20, 30, 32 and 34 which 
move in the direction shown by the arrows shown in rollers 22, 31, 35 and 
36. As the baling chamber fills, the outward pressure of the compressed 
crop strands stretches the belts taut so that they assume the 
configuration shown in FIG. 2. As the baling chamber becomes full, 
compressive forces exerted on the bale tend to force the tailgate open. An 
appropriately calibrated sensor can be incorporated into the latch 
assembly to signal that the bale is ready for discharge. 
When the "chamber full" status is sensed, the operator stops the forward 
motion of the tractor, terminating pickup from windrow 16, thereby 
allowing the crop material at the pickup reel 18 to be carried on into the 
baling chamber. This done, the bale tying sequence is begun either 
manually or automatically using spools of twine carried in storage box 73 
(See FIG. 1). On completion of the bale tying event hydraulic cylinder 42 
is actuated to move the upper subframe 40 from the FIG. 2 to the FIG. 5 
configuration. 
Actuation of hydraulic cylinder 42 does the following. The movable shaft of 
hydraulic cylinder 42 is secured by pin means to pivot 62. Offset from 
this pin means is a second pin mounting means 80 which secures pivot 62 to 
subframe 40. Clevis 82 is depicted as the pin mounting means between shaft 
43 of hydraulic cylinder 42 and pivot 62. With hydraulic cylinder 42 
attached between subframe 40 and the mainframe of the baler in the manner 
depicted in FIG. 2, initiation of the piston withdrawing action, first 
causes pivot 62 to rotate in a clockwise direction as viewed in FIG. 2. 
Rotation of pivot 62 clockwise causes a pull to be exerted on cable 60 
which is secured to the upper end of the pivot. A pull on cable 60 exerts 
through crankarm 58 a torque on torque arm 46 which unlatches latch plates 
50 and 52 from pins 56. 
With the two latch arms released, the hydraulic cylinder can complete the 
rotation of subframe 40 about the axle shaft of roller 36. Retraction of 
piston shaft 43 raises the tailgate to the FIG. 5 condition. With the 
baler positioned as shown in FIG. 5, the tied bale 38 is ready for 
ejection out the back of the baler. Subsequent to ejection, the tailgate 
can be reclosed by extension of shaft 43 of hydraulic cylinder 42. As 
shaft 43 reaches its openmost position, its length is such that pivot 62 
is rotated counterclockwise to a position which allows springs 54 to draw 
latch plates 50 and 52 into the engaged position depicted in FIG. 1. 
When this tailgate closing event is completed, the alert light will be 
extinguished signifying to the operator that he can restart the tractor to 
gather hay for making another bale. 
The ejection of bale 38 from the depression formed when belts 20 conform to 
the placement of rollers 24, 26 and 28 requires the introduction of a 
coupling force synchronized with the opening of tailgate 44. The need for 
the coupling force comes about since the bale sets in a depression formed 
by placing roller 24, 26 and 28 on the circumference of a circle. This 
placement creates the tendency for bale 38 to continue rotating in place 
when tailgate 44 opens to the FIG. 5 configuration. By introducing bale 
contacting means (not shown) subsequent to the opening of tailgate 44, the 
bale can be made to stop rotating about its central axis. This application 
of a coupling force transfers the center of rotation from the bale axis 
toward the upward periphery, thereby allowing the bottom conveyor belts 20 
to move the bale rearward and out of the baler. As soon as the center of 
mass passes beyond roller 28, gravity will take over and the bale will 
roll downward over rear frame member 71. 
As it drops to the ground, bale 38 assumes the position shown in FIG. 3. 
During the discharge event forward motion of baler 10 has been stopped. 
Therefore, after bale 38 drops to the ground it will remain at a fixed 
distance from the rear of the baler. Cross rear frame member 71 keeps the 
bale clear from moving belts 20 and roller 28. Additionally, the bale is 
clear of those areas of the baler with which tailgate 44 mates. This means 
that as soon as bale 38 is discharged, tailgate 44 can be closed by 
extending the shaft of hydraulic cylinder 42. With the tailgate closed and 
latches 50 and 52 secured, the operator can restart the forward motion of 
the tractor to initiate pickup of crop material 16 from the windrow. 
This differs from what can be done with the prior art baler shown in FIG. 
4. The FIG. 4 baler has a bottom conveyor belt assembly 96 which is 
basically the same as that of the FIG. 3 baler. The FIG. 4 baler comprises 
a single axle chassis 70 having a tow bar tongue 72 extending out the 
front for attachment to a tractor or similar vehicle. The upper structure 
is comprised of skeletal members onto which sheets of metal are secured. 
There is a front part 74 and a rear part 76. Together, they form a 
horizontal, generally cylindrical baling zone. Rear part 76 is hinge 
mounted to front part 74 by means of a pivot bearing at the topmost one of 
the rollers. This allows the rear part 16 of the baler to be swung upward 
approximately 90 degrees when discharging a completed bale 94. 
Latch 80 can be released when the baling chamber is full. With the latch 
released, hydraulic cylinder 84 can be extended to open the tailgate since 
the cylinder ends are anchored to the baler sidewalls by pins 86 and 88. 
With the tailgate open to the FIG. 4 configuration the bottom conveyor 
assembly continues to move in the direction shown by arrow 92 carrying 
bale 94 past rear roller 90 and causing it to drop to the ground as shown. 
Since bale 94 drops down just back of the baler, it comes to rest under 
the overhanging tailgate. Before the tailgate can be closed the prior art 
baler must be moved ahead by at least the width of the bale. 
To accomplish the step of having to move the baler ahead almost ten feet 
before the tailgate can be closed after discharging a bale, the operator 
of the prior art baler has to do extra work. When the bale is ready for 
discharge, the operator stops the forward motion of the tractor along the 
windrow, shifts it into reverse, backs up eight-to-ten feet and initiates 
the discharge sequence. When the bale is discharged, as shown in FIG. 4, 
the operator drives ahead a few feet, stops and initiates the tailgate 
closing sequence. When the tailgate is closed, the operator can then 
restart the tractor to undertake pickup of crop material for the next 
bale. If the operator of the prior art baler does not backup before 
discharging a bale, crop material from the windrow is encountered when the 
baler is moved ahead to provide clearance for the downswinging tailgate. 
Any crop material picked up while the tailgate is open will pass on 
through the baler. 
With applicants' baler there is no need to backup the machine to obtain 
clearance for closing the tailgate. As soon as the bale strikes the 
ground, as shown in FIG. 3, the tailgate can be reclosed. The reason the 
tailgate can be reclosed immediately after bale discharge has to do with 
the placement of the pivot. The upper section (See FIG. 2) pivots relative 
to the lower section at the shaft of roller 36 to open and close the 
cavity. The pivot location is elevated relative to rear frame member 71 so 
that it is below the intersection of diameter 99 which joins the rear 
frame member 71 and the central axis of the bale cavity with the front 
periphery of the bale cavity. The avoidance of machine backup saves both 
time and wear on the clutch mechanism of the tractor used to pull the 
baler. 
Applicants discovered that all conveyor assemblies above the bottom 
conveyor could be incorporated into the subframe which is hinge mounted 
along one edge. Reference to FIGS. 2 and 6 shows that more than half of 
the periphery of bale 38 is circumscribed by the conveyor assemblies 
mounted in the upper section. Line 39 in FIG. 6 passes through both front 
roller 36 and the center of bale 38. As such line 39 coincides with a 
diameter of the bale which is seen to be greater than the spacing between 
roller 29 and 36. When the tailgate opens to the FIG. 5 configuration, the 
conveyor assembly containing belts 30 and roller 29 must slip past the 
full cross-section of the bale. For this to happen, the bale must be 
sufficiently compressible so that the instantaneous diameter of the bale 
in the fore to aft dimension does not exceed the spacing between rollers 
29 and 36. 
Several factors contribute to the release of the bale. One is the bale's 
weight which is usually in excess of a quarter of a ton. Another is the 
fact that the contacting belts are moving, hence one is dealing with 
friction and does not have to include breakaway forces which some call 
stiction. Third, the baling action in the chamber is such that most crop 
strands are oriented circumferentially around the bale. As a result, the 
release of the bale by the upper section of conveyor is such that slippage 
is lengthwise along the crop stems which minimizes binding due to bunching 
of crop material. Fourth and probably most important the bale is able to 
flex. Pressure applied across one diameter results in the bale assuming a 
slightly elliptical cross section. 
Our discovery that a tightly packed bale of crop material could still be 
flexed made it possible to configure a baler having a tailgate which opens 
like a clam shell. The upper section being hinged at the front has a 
rearward facing tailgate which raises upward for discharge by an amount 
which exceeds the diameter of the bale. In the machine reduced to 
practice, four foot diameter bales were produced. 
While the invention has been described in conjunction with a baler which 
forms large round bales in a chamber of fixed size, it will be understood 
that it can be of equal utility in other embodiments. Various changes in 
the details, materials, steps and arrangement of parts may be made and 
will occur to those skilled in the art upon a reading of the above 
disclosure. Therefore, the invention should not be limited to the specific 
illustration disclosed, but only by the following claims.