Apparatus for making round bales

A round baler having a main frame including opposing sidewalls, and an apron assembly comprising crop engaging elements disposed between said sidewalls for defining a bale forming chamber having a fixed generally cylindrical shape with a transverse inlet. The crop engaging elements move along a path having an inner course contiguous with a major portion of the fixed periphery of the cylindrical chamber, and a pickup assembly for feeding crop material to the chamber through the inlet whereby crop material accumulated in the chamber is engaged by the crop engaging elements and formed into a compacted cylindrical package under conditions where a sufficient amount of crop material has accumulated in the chamber. A supply of net material is dispensed via a dispensing assembly having grasping elements for feeding the net into the chamber for wrapping the periphery of the cylindrical package of crop material in the chamber to form a round bale of crop material. The dispensing assembly is mounted on the main frame to pivot about a fixed pivot for moving the grasping elements between a retracted position remote from the cylindrical chamber and an extended position adjacent the cylindrical chamber for dispensing net between the peripheral surface of the compacted cylindrical package of crop material and the crop engaging elements.

FIELD OF THE INVENTION 
This invention relates generally to apparatus for making cylindrical bales 
of crop material, commonly referred to as a round baler. More 
particularly, this invention pertains to a wrapping assembly for wrapping 
crop material that has been formed into a cylindrical package in a round 
baler having a fixed forming chamber. 
BACKGROUND OF THE INVENTION 
Prior art balers generally have a bale forming chamber defined by an apron 
comprising an array of side-by-side belts, transverse slats trained on 
chains, a plurality of rolls or a combination of these various elements, 
e.g., rolls and belts. Crop material, such as hay, is picked up from the 
ground as the baler traverses the field, fed into a fixed or variable 
chamber where it is accumulated and compressed to form a cylindrical 
package of crop material. The formed package, while in its compacted 
condition inside the chamber, is wrapped with net, plastic film, twine or 
the like, to produce a completed round bale that is then ejected from the 
chamber onto the ground for subsequent handling. 
Exemplary of prior art round balers of the type referred to above having a 
fixed chamber, i.e., a bale forming chamber that does not vary in size, 
are the various balers disclosed in U.S. Pat. No. 4,176,596, issued Dec. 
4,1979 in the name of Hans O. Sacht, No. 4,212,149, issued Jul. 15, 1980 
in the name of Bernard Krone et al, and 4,599,844, issued Jul. 15, 1986 in 
the name of Gerhard Clostermeyer et al, each of which illustrates a 
different type of apron assembly. In U.S. Pat. No. 4,176,596 a baler is 
disclosed in which the bale forming chamber is defined by a plurality of 
similar groups of side-by-side conveyor belts arranged around the 
periphery of the chamber. The conveyor comprises a pair of opposing chains 
between which a plurality of parallel crop engaging slats are mounted. The 
chamber in U.S. Pat. No. 4,212,149 is defined by a continuous slatted 
conveyor in combinations with a pair of floor rolls, in which an inner run 
of the conveyor is guided along a fixed path along a major portion of the 
periphery of the chamber. A third type of apron assembly, shown in U.S. 
Pat. No. 4,599,844, consists of a plurality of adjacent rolls arranged 
transversely in a generally circular array to define a cylindrical 
chamber. 
Various wrapping systems employ known wrapping materials, such as net or 
twine, to wrap compacted packages of crop material formed in fixed chamber 
round balers. For example, the Sacht and Krone et al patents, mentioned 
above, refer to commonly accepted twine wrapping systems for completing 
bales formed in the balers disclosed. In another patent directed to a 
fixed chamber defined by transverse slats mounted on chains, U.S. Pat. No. 
4,610,123, issued Sep. 9, 1986 in the name of Bernard Krone et al, a 
system is disclosed whereby net wrapping material is used. In this baler 
the net is introduced into the fixed chamber via the transverse inlet 
through which crop material is fed. 
In the baler disclosed in the Clostermeyer et al patent, mentioned above, 
net wrapping is accomplished by introducing net into the forming chamber 
via a path between a pair of adjacent rolls in the circular array defining 
the chamber. Another example of this is illustrated in U.S. Pat. No. 
4,580,398, issued Apr. 8, 1996 in the name of Dirk Bruer et al. 
Although twine wrapped bales are common and readily acceptable, many 
farmers prefer to use net for various reasons, e.g., less losses in 
certain crop conditions, a smoother outer surface on the completed bale 
which gives added protection against rain, and reduced field time for 
wrapping due to the reduced number of revolutions of the completed package 
in comparison to twine wrapping. Regardless of the wrapping medium, in a 
fixed chamber baler, as in most variable chamber balers, initiation of the 
wrapping step is not commenced until a cylindrical package of crop 
material has been fully formed and compacted in the chamber at which time 
the tail of the twine or net is introduced to the chamber between the 
forming elements of the apron or through the crop inlet. The twine or net 
is retained between the outer surface of the compacted cylindrical package 
of crop material and the apron, and due to frictional force the wrapping 
material encases or encircles the package as it continues to rotate in the 
chamber. Finally, the wrapping process is completed, the net or twine is 
severed, and a completed bale is discharged from the chamber. 
In the past, problems have been encountered in attempts to consistently 
introduce wrapping material to the chamber. Especially in the case of net 
where a tail of material the width of the package is desirably introduced 
simultaneously and evenly across the entire width of the forming chamber 
for efficient and effective wrapping. As mentioned above one of the 
principal advantages of net wrapping is the ability to reduce wrapping 
time. This is accomplished by limiting the number of revolutions of the 
completed package in the chamber during wrapping to 2 or 3 which is a 
significant contribution to reduction of the overall elapsed time in the 
bale forming process as compared to twine where ten times that number 
would not be uncommon, depending on crop material and bale size. However, 
a key to successfully achieving this important advantage is feeding an 
even tail into the chamber in a consistent and uniform fashion, and 
severing the net in a manner that enables subsequent wrapping to be 
initiated effectively. 
SUMMARY OF THE INVENTION 
An important object of the present invention is to provide wrapping 
apparatus for a fixed chamber round baler that consistently introduces a 
web of wrapping material to the chamber in a manner that enhances 
reliability and thereby improves overall performance. 
In pursuance of this and other important objects the present invention 
provides for new and unique improvements to a round baler for forming crop 
material into cylindrical bales, comprising opposing sidewalls, means 
defining a bale forming chamber having a fixed generally cylindrical shape 
with a transverse inlet, the defining means including an apron assembly 
comprising crop engaging means disposed between the sidewalls, means for 
supporting the apron assembly on the main frame, means for moving the crop 
engaging means along a path contiguous with a portion of the fixed 
periphery of the cylindrical chamber, means for feeding crop material to 
the chamber through the inlet whereby the crop material accumulated in the 
chamber is engaged by the crop engaging means under conditions where the 
crop material engaging means are moving along a portion of the periphery 
to engage the crop material and form it into a compacted cylindrical 
package when a sufficient amount of crop material has accumulated in the 
chamber, and a supply of web material. More particularly, the invention 
contemplates a dispensing assembly including insertion means for 
dispensing the web material into the chamber for wrapping the periphery of 
the cylindrical package of crop material to form a round bale of crop 
material, the insertion means including grasping means for transversely 
engaging the web material, and means for mounting the dispensing assembly 
on the main frame to pivot about a fixed pivot for moving the grasping 
means of the insertion means between a retracted position remote from the 
cylindrical chamber and an extended position adjacent the cylindrical 
chamber for dispensing the web material between the peripheral surface of 
the compacted cylindrical package of crop material and the crop engaging 
means. 
The foregoing and other objects, features and advantages of the invention 
will appear more fully hereinafter from a consideration of the detailed 
description which follows, in conjunction with the accompanying sheets of 
drawings wherein one principal embodiment of the invention is illustrated 
by way of example. It is to be expressly understood, however, that the 
drawings are for illustrative purposes and are not to be construed as 
defining the limits of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings for a more detailed description of the 
preferred embodiment of the invention, FIG. 1 shows a fixed chamber round 
baler 10 of the type disclosed in U.S. Pat. No. 4,212,149, discussed 
above. As will become apparent from the following description, the present 
invention is directed to improved apparatus for wrapping a cylindrical 
package of crop material formed in a fixed chamber type round baler, a 
typical example of which is baler 10. More particularly, the wrapping 
apparatus generally comprises a dispensing assembly 11 and a net severing 
assembly 12 for dispensing and cutting web material, such as net, issued 
from a supply roll 13. 
Round baler 10 includes a main frame 14 with a main support beam 15 on 
which a pair of wheels 16 (only one shown) are rotatably affixed. The main 
frame includes a pair of side walls between which a cylindrical bale 
forming chamber extends. For the purposes of clarity only one wall 17 is 
shown throughout the drawings and the elements mounted inwardly thereof 
are shown in full lines for clarity, which is an approach not uncommon in 
the descriptions in prior art patents. For illustrative purposes reference 
letter B is used to designate a bale, shown in cross section in the 
chamber. 
Baler 10 also includes a tongue 18 extending from the forward portion of 
main frame 14 for conventional connection to a tractor. Pivotally 
connected to the sidewalls of main frame 14 by a pair of stub shafts 20 is 
tailgate 21 which may be closed, as shown throughout the drawings, during 
bale formation or pivoted open about stub shafts 20 to discharge a 
completed bale. The tailgate includes tailgate walls 22 coextensive with 
side walls 17. A pickup assembly 23 mounted on main frame 14 in a suitable 
manner includes a plurality of fingers or tines 24 moveable in a 
predetermined path to lift crop material from the ground, generally 
depicted by direction arrow a, and deliver it rearwardly (arrow b) toward 
a transverse inlet 25 in the chamber defined by a floor roll 26 and a 
transverse stripper roll 27, both of which rolls are rotatably supported 
on mainframe 14 between sidewalls 17. 
The bale forming chamber is defined primarily by an apron assembly 28 
comprising a pair of support chains 30 mounted to travel along a 
continuous path, the inner run of which is defined on sidewalls 17 and 
tailgate walls 22 by front and rear sections 31, 32 of a continuous chain 
guide track that separates during bale discharge. The apron further 
comprise a plurality of parallel tubular crop engaging slats 33 extend 
between chains 30 to provide a cage-like periphery of the cylindrically 
shaped chamber. Radially outwardly of the inner run of apron assembly 28 
are front and rear sections 34, 35 of continuous cylindrical bale chamber 
wall. These sections, also separable during bale discharge are mounted 
between side walls 17 and tailgate walls 22 for maintaining integrity 
between the outer and inner runs of chain 30. Operatively engaged with 
chain 30 are drive sprocket 26 mounted between sidewalls 17, idler 
sprockets 37 also mounted between sidewalls 17 on shaft 20, and idler 
sprocket 38 mounted between tailgate walls 22. A conventional chain drive 
system for drive sprocket 36 is provided via appropriate coupling to 
gearbox 40 in a conventional manner, diagrammatically depicted in phantom 
outline outwardly of sidewall 17. The bale forming chamber is further 
defined by the outer conveying surfaces of floor roll 26 and stripper roll 
27, both of which are driven in a clockwise direction by conventional 
drive means appropriately coupled to gear box 40. These rolls are provided 
with ribs 41, 42 to enhance their ability to convey crops in the chamber 
as a bale is being formed. Other forms of aggressive surface structure may 
be used to accommodate various types of crops and conditions. 
Now turning to FIG. 2 for a more detailed description of the wrapping 
apparatus of the present invention which comprises dispensing assembly 11 
shown in the fully retracted position, and net severing assembly 12, which 
assemblies are cooperatively adapted to dispense net n from net supply 
roll 13 and severe such net, respectively. 
Dispensing assembly 11 comprises a pair of parallel frame members 43 
fixedly secured to rotatably supported cross tube 44 that extends between 
sidewalls 17, and upper and lower clamping members 45, 46, respectively, 
both of which have tips for grasping net n in a fashion that is clearly 
described in U.S. Pat. No. 4,956,968, issued Sep. 18, 1990 in the name of 
Kenneth R. Underhill, hereby incorporated by reference. 
Net severing assembly comprises a shear bar 47 fixedly mounted between 
sidewalls 17, and a transverse knife 48 affixed to a mounting member 49 
extending between a pair of parallel knife support arms 50 rotatably 
mounted at fixed pivots 51 on the inside surface of sidewalls 17. A 
coupling link 52 is pivotally attached at one end to dispensing assembly 
frame member 43, and at its other end to knife support arm 50. 
Mounted outboard of sidewall 17 is an electrical actuator assembly 53 
comprising means for reciprocally driving element 54, which is pivotally 
attached to one end of a link 55. It should be noted that the function of 
actuator assembly 53 could be accomplished equally as well with a 
hydraulic cylinder or other equivalent mechanisms. The other end of link 
55 is fixedly attached to cross tube 44. Also fixedly attached to cross 
tube 44 is a link 56 which is coupled to rod 57 via a sliding yoke 58. Rod 
57 has a freely swingable lower end that moves in response to the position 
of link 56 which determines the position of yoke 58 along its shank. Thus 
the upper end of rod 57, which is affixed to a leg 60, pivots about its 
pivot 61 in response to the swing of lever 56 about pivot 62. Cushioning 
springs 63, 64 absorb the impact of yoke 58 during its traversal along rod 
57. 
Affixed to and pivoting with leg 60 is drag arm 65, to the outer end of 
which is attached drag shoe 66 held in contact with the outer surface of 
net supply roll 13 by spring 67. In a manner similar to that which is 
taught by U.S. Pat. No. 5,243,806, issued Sep. 14, 1993 in the name 
Richard E. Jennings et al, hereby incorporated by reference, the net is 
issued from supply roll 13 along a path around idler roll 68 and spreader 
rolls 71, 70 and thence to clamping members 45, 46. 
In operation net dispensing assembly 11 moves from the fully retracted 
position shown in FIGS. 1 and 2 to its intermediate position shown in FIG. 
3. This is achieved when actuator element 54 is thrust outwardly, as 
indicated by direction arrow c, which rotates frame members 43 counter 
clockwise, causing net severing assembly to rotate clockwise and release 
the end of the net from between knife 48 and shearbar 47 where it was 
being held during the formation of a compacted cylindrical package in the 
chamber. Net tail t is guided toward the insertion space between roll 27 
and 1 shield element 72 as the compacted package of crop material rotates 
in the chamber in direction d past such space. Element 72 comprises a 
rigid sheet of material extending between sidewalls 17 to shield apron 28 
which is moving away from the chamber. The passage of ribs 42 on roll 27 
past the opening between roll 27 and shield 72 creates air currents that 
tends to pull tail t toward the chamber which causes a fluttering effect 
in the net illustrated by the generally extended position of the limp end 
of the net n depicted in FIG. 3. This enhances the initiation of net 
wrapping. 
FIG. 4 shows the dispensing assembly in the fully extended position during 
wrapping. Drag shoe 66 has been released to allow net to be freely issued, 
i.e., shoe is not in contact with the surface of net supply roll 13. In 
the event some drag is desirable during wrapping this shoe can be adjusted 
for varying frictional engagement. When the tail engages the surface of 
the cylindrical package it is pulled to the nip formed by the roll and the 
rotating package and thence dragged around periphery to envelope the 
cylindrical package of crop material in a known manner. Even without the 
flutter phenomena, tail t of net n is positively inserted to the vicinity 
of the nip mentioned above under conditions where the dispensing assembly 
reaches its fully extended position shown in FIG. 4 to start the wrapping 
sequence, i.e., net is pulled from the supply roll and dispensed to the 
chamber. 
After 2 or 3 wraps (or more, if desired) have been applied in this fashion, 
dispensing assembly 11 is withdrawn via an intermediate position (FIG. 5) 
by retraction of actuator element 54 causing frame members to rotate 
clockwise which in turn pulls severing assembly upwardly toward net n 
being dispensed along a path adjacent to shearbar 47. When the fully 
retracted position of FIGS. 1 and 2 is attained net n is severed by knife 
48 which holds the end of the net tail t against shear bar 47 until the 
next wrapping operation is initiated. 
In summary, included among the many advantages, explicit and implicit, of 
the unique apparatus described herein is the provision of a fixed chamber 
round baler with overall enhanced operation due to the incorporation of 
wrapping apparatus comprising a dispensing assembly and a severing 
assembly that cooperate in a manner to provide reliable net insertion with 
minimal time requirements. 
While the preferred structure in which the principles of the present 
invention have been incorporated is shown and described above, it is to be 
understood that the invention is not to be limited to the particular 
details, as shown and described above, but that, in fact, widely different 
means may be employed in the practice of the broader aspects of the 
invention.