Apparatus for harvesting of field-fodder

In an agricultural pick-up baler, forming rectangular bales of harvested agricultural material or field fodder like hay, straw, grass-silage, the agricultural material is loaded to a compressing device shredding and crushing the fodder to a highly densified tough layer, urged to a baling chamber via a press channel. The fed-in position of the layer is then additionally densified and compacted at its flat side by a pressing plate against the resistance of friction within the baling chamber with simultaneous extruding said rectangular bale through a rear discharge opening of said baling chamber. By the method and apparatus according to the invention properly shaped and highly densified bales are produced with relatively light-weighted and simple-driven compacting structural elements. Thus, the massive and expensive pitman-and-crank-assembly of conventional balers can be avoided.

FIELD OF THE INVENTION 
The present invention generally relates to agricultural crop balers and, 
more particularly, to a method and an apparatus for harvesting of 
agricultural material like hay, straw, grass-silage or corn wherein the 
material is picked-up from the ground, compressed by a tine-drum and 
loaded into a baling chamber to form a rectangular bale. 
BACKGROUND OF THE PRIOR ART 
Most of so-called large or big square balers in use work according U.S. 
Pat. No. 4,372,104, wherein a pick-up device loads harvested agricultural 
material into a supply passage, connected to the inlet opening of a 
compressing channel. A pressing ram is reciprocated back and forth in a 
horizontally arranged compressing channel by at least one plunger for 
compacting the material to a big square bale up to a weight of one ton. 
Usually, the drive assembly of the plunger is a pitman-and-crank-assembly 
coupled to a gear-box, as shown in U.S. Pat. Nos. 4,525,991 or 4,782,651, 
respectively. These drive means are rather voluminous and have many 
components, thus being relatively expensive to produce. 
The agricultural material is moved through the supply passage to the 
compressing channel by a conveying or feeding device extending into the 
supply passage with a plurality of fork-like fingers or tines. The crop 
entering the compressing channel, is only partially compressed by the 
tines of this feeding device, and oscillates in a kidney-shaped path of 
travel. Thus the main compacting work has to be done by said pressing ram, 
which has to be very strongly built. Furthermore, the drive means of the 
feeding mechanism is rather complicated. 
As the agricultural material has a certain elasticity when compressed, the 
compressed material re-expands upon the return movement of the 
reciprocating ram. Thus, with this method the material is compressed 
several times, causing a loss of energy, and the degree of compression is 
relatively low due to the re-expansion of the material. 
The German Patent No. 34 45 015 discloses a rotary compressing drum with 
tines, the tips of which engage grooves in the drum casing, thus shredding 
and crushing the material. In this way a densified layer is produced, 
which is accumulated in a box to a rectangular bale. 
Although the degree of compression is higher than with the above-mentioned 
usual big balers, it is desirable to improve the density to achieve highly 
densified bales which may be transported and stored within a minimum 
space. 
Furthermore, the forming of a rectangular bale according to the German 
Patent No. 34 45 015 is very complicated, as the layers are piled up in a 
generally vertical box by lowering the ground-plate of this box 
step-by-step. Thus, the size of the accumulated bale is very difficult to 
change. After forming one big bale consisting of about ten to twenty 
layers the ground-plate has to be lifted in only a few seconds, as the 
feeding of the material is continuous. The doors of the box have to be 
opened and the knotting device has to be operated by a very complicated 
hydraulic control circuit. Thus, continuous, fast operation of the 
crop-baler is very difficult to achieve. 
SUMMARY OF THE INVENTION 
It is a primary object of the present invention to provide a method for 
harvesting of agricultural material achieving a higher compression of the 
material in a continuous, fast operation of a crop-baler. 
It is a further object of the invention to provide an apparatus for 
harvesting of agricultural material, achieving a high compression without 
re-expansion of the bale. 
It is further object of the invention to provide a compact design of the 
baler and drive means having a small number of components. 
It is another object of the invention to provide a bale forming apparatus 
allowing the quick and simple change of the bale size. 
Still another object of the invention is to provide a baler allowing 
continuous, fast operation in the field. 
SUMMARY OF THE INVENTION 
These and other objects are obtained by a method for harvesting of 
field-fodder and forming substantially rectangular bales thereof in a 
baling chamber, comprising the steps of picking-up said field-fodder from 
the ground, compressing said field-fodder by shredding and crushing 
thereof between tines of a compressing drum and grooves of a drum casing 
to a highly densified layer; urging said densified layer through a press 
channel to an inlet opening of said baling chamber; further compressing 
said layer at a flat side thereof against the resistance of friction 
within said baling chamber with simultaneous extruding of said rectangular 
bale through a rear discharge opening of said baling chamber. 
According to another aspect of the invention there is provided an apparatus 
for harvesting of field-fodder like hay, straw, grass-silage and forming 
substantially rectangular bales thereof in a baling chamber comprising: 
pick-up means for picking up said field-fodder from the ground; a 
compressing drum provided with tines engaging grooves of a drum casing and 
a slotted top wall of a press channel for shredding and crushing said 
field-fodder picked up by said pickup means to a highly densified layer; 
a press channel forming an output of said compression drum, having a 
slotted portion for permitting passage of said tines and conveying said 
layer formed in said compression drum by further densifying said layer 
through an inlet opening into said baling chamber; and 
a pressing plate arranged at an end surface of said baling chamber and 
movable in said baling chamber in a longitudinal direction of said baling 
chamber for pressing said layers accumulating in said baling chamber in 
said direction toward an discharge opening of said baling chamber. 
As the result of this method and apparatus according the invention the 
already densified layer is further compressed and compacted at its flat 
side thus increasing the degree of density of the rectangular bale. Since 
the agricultural material fed into the baling chamber is already 
pre-densified by the compressing drum and the press channel the drive 
means of the compressing plate may be designed to be simple and less 
strong. By further compressing the layer at its flat or main side, a 
re-expansion is avoided since in contrast to the known big balers the crop 
material is not loosely fed into the baling chamber but as a 
high-densified layer. In contrast to the apparatus of the German Patent 
No. 34 45 015 the dimensions of the rectangular bale, especially the 
length of the bale, may be easily changed by varying the number of 
compressed layers. 
With this method and apparatus it is not necessary to use haydogs or the 
like as they are used in connection with the bale chamber in U.S. Pat. No. 
4,782,651 for holding a freshly compacted charge of material against 
retrograde movement after being pressed rearwardly by the plunger, because 
the highly densified layer which is cut off near the inlet opening does 
not re-expand. 
Due to this method the layers and the resulting rectangular bale remain 
well shaped and form fitting, thus enabling a high degree of compression 
to be achieved with low energy expenditure. 
In a preferred embodiment, the main compression by the tine-drum 
arrangement is very high, so that the layer in the press-channel will not 
be compressed in longitudinal direction anymore. To enable a continuous 
operation of the crop baler during the forward movement of 
compressing-plate into the baling chamber there is provided a slotted 
lateral wall, which is displaceable in a longitudinal direction of that 
press channel, thus interrupting the supply of the high-densified layer to 
the press channel by the compressing-drum. 
Another possibility to reach continuous operation is to form the 
compressing plate of two or more telescopable parts which may be moved in 
longitudinal direction of said press channel. In this way the further 
compressed rectangular bale is held in its position whilst the layer is 
fed from the press channel into the baling chamber without any 
interruption.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 shows a preferred first embodiment of a baler according to the 
invention, comprising a frame 1 on which is mounted a pick-up device 2 for 
taking up the field-fodder from the ground with the baler travelling over 
the field. The crop is transferred to a center gathering auger 3 with a 
central packing device 4 to supply the crop to the compressing device 5. 
The latter consists of a drum 6 provided with radially projecting tines 7 
arranged in a twisted winding around the drum 6. The tips of the tines 7 
engage with a plurality of grooves 9 formed in a drum casing 8. For 
further details of this arrangement and the design of the press-channel, 
reference may be had to the German Patent 34 45 015. 
The field-fodder crushed and shredded in this compressing device 5 is fed 
by the drum 6 into a press channel 10 which is formed by a slotted wall 11 
(shown in FIG. 5-8), an adjustable bottom wall 12 and side walls 16. 
Adjusting means for adjusting the bottom wall 12 and/or a wall 15 which is 
an extension of the slotted wall 11 are enumerated with 13 and 14. These 
adjusting means 13,14 are used to vary the cross-section of the press 
channel 10 in order to vary the density of the layer, which is output by 
the compressing device 5. 
Extending the press channel 10 a buffer-part 17 is provided to store the 
compressed layer when an inlet opening 21 of the baling chamber 23 is 
closed. Preferably the length of said buffer-part 17 of the press channel 
10 corresponds to the height of the baling chamber 23. In this buffer-part 
17 of the press channel 10 a conveying device 18 having forks 19 may be 
arranged for additional urging the layer into the baling chamber 23. This 
conveying device 18 is not absolutely necessary for the operation of the 
crop baler, as it may be gathered from FIG. 4 to FIG. 8, wherein the press 
channel 10 is designed without any conveying device 18. In the embodiment 
according to FIG. 1 the conveying device 18 transfers a compressed layer 
stored in the buffer-part 17, into the baling chamber 23 through its inlet 
opening 21, when detected by a detector 20. 
The baling chamber 23 has a rectangular cross-section and is fixed on the 
frame 1, extending generally horizontally to a rear discharge opening of 
the baling chamber 23. After transferring said layer through the inlet 
opening 21, the layer is pressed towards the rear discharge opening by the 
compressing-plate 22, which is reciprocable by distance corresponding to 
the width of the layer which in turn corresponds to the width of the press 
channel 10. By moving to the right in FIG. 1, the compressing plate 22 
presses against the flat or main side of the layer against the resistance 
of friction within said baling chamber 23 increasing the density of the 
layers and the rectangular bale 24 formed thereof. When the rectangular 
bale 24 reaches the desired length, which is nearly the length of the 
baling chamber 23 (see FIG. 1), a knotting device 25 and a knotting needle 
26 is actuated as shown in FIG. 1. It may be gathered from FIG. 1, that a 
first rectangular bale 24 is just being knotted, whilst (on the right 
portion of FIG. 1) a second rectangular bale 24 is extruded through the 
discharge opening of the baling chamber 23. This is also shown in FIG. 2, 
wherein four twines, which may be of sisal, plastic or wire, are wound 
around the second bale 24, just leaving the baling chamber 23. 
FIG. 2 illustrates the baler of FIG. 1 in a plan view, especially showing 
the arrangement of the tines 7 in a twisted winding and the cross-section 
of the press channel 10. Further, the cross-section of the layer, formed 
in this press channel 10, may be gathered from this view. 
According to FIG. 3 the press channel 10 is arranged generally horizontally 
to reduce the overall height of the baling apparatus. In contrast to the 
embodiment of FIG. 1 the conveying device 18 is designed as a rotary 
conveyor with two forks 19, engaging the kidney-shaped press channel 10 
alternatively on command of the detector 20, as a variation of the chain 
conveyor in FIG. 1. The compressing plate 22 in this embodiment is guided 
by a roller guide 27, instead of a lever guide in FIG. 1. 
FIG. 4 shows a preferred embodiment of the invention without the conveying 
device 18 of FIG. 1 or 3. Here the compressing drum 6 urges the compressed 
layer directly through the relatively short press channel 10 into the 
baling chamber 23. Consequently, the detector 20, initializing the 
movement of the compressing plate 22 is arranged at the upper side of the 
baling chamber 23. The compressing plate 22 is guided by swing-levers 28 
to ensure the reciprocating movement of the compressing-plate 22 forth and 
back, as indicated by phantom lines. 
FIG. 5 shows a further embodiment having a similar configuration as in FIG. 
3, wherein the compressing plate 22 is shown in its retracted position; 
thus the layer formed in the press channel 10 may be urged into the baling 
chamber 23. 
According to FIG. 6 the compressing plate 22 pressing at the flat or main 
side of the layer is shown in its forward compressing position. Since in 
continuous operation further field-fodder is compressed between the tines 
7 of the drum 6 and the grooves 9 in the drum casing 8 and compacted in 
the press channel 10, the layer in the press channel 10 might be 
over-densified. To prevent this, the slotted wall 11 may be lifted while 
the inlet opening 21 to the baling chamber 23 is closed by the bottom of 
the compressing plate 22, thus expanding the volume of the press channel 
10. By this measure, the layer in a short press channel 10 is not over 
densified, as the crop fed to the compressing device 5 is not further 
compacted but merely conveyed around the drum 6 in the portion 8a of the 
drum casing, whilst the inlet opening 21 of the baling chamber 23 is 
closed. 
The same purpose is obtained by the design according FIGS. 7 and 8, where 
the compressing plate 22 consists of two parts 29,30, the lower part being 
telescopable within the upper part 30 or vice versa. The lower part 29 is 
lifted by the compressed layer continuously fed out of the press channel 
10 during the compressing plate 22 remains in its forward position 
according FIG. 6. The lower part 29 is guided in roller bearings 31 
arranged within the compressing plate 22, which is actuated by a hydraulic 
jack 32. After retrograde movement of the compressing plate 22 along a 
guide-rail 34 to the position according FIG. 5 by contracting of the 
hydraulic jack 32 , the lower part 29 of the compressing plate 22, which 
was lifted by the fed-in layer, is lowered by a second hydraulic jack 33 
and a pair of lateral levers 35 or by gravity. In this configuration the 
rectangular bale 24, formed of several layers fed out of the press channel 
10 is under permanent compression either by the compressing plate 22 
itself or by the partially fed-in layer, thus preventing re-expansation of 
the rectangular bale 24. 
As explained above, by the method and apparatus according to the invention 
properly shaped and highly densified bales are produced with relatively 
light-weight and simple compacting means. Thus, the very massive and 
expensive pitman-and-crank-mechanism of conventional balers necessary to 
apply a compression pressure of about 800 pounds per square foot can be 
avoided. 
Still other objects and advantages of the present invention will become 
readily apparent to those skilled in this art from the preceding detailed 
description, wherein only the preferred embodiments of the invention are 
illustrated and described, as aforementioned, simply by way of presenting 
the best modes contemplated of carrying out the invention. As will be 
realized, the invention is capable of other and different embodiments, and 
its several details are capable of modifications in various obvious 
respects, all without departing from the invention. Accordingly, the 
drawing and description are to be regarded as illustrative in nature, and 
not as restrictive, the invention being defined solely by the claims 
appended hereto.